Diekman, a reliever who's made 285 MLB appearances since 2012, isn't on this assignment because of poor performance. Tommy John surgery didn't force him to miss time on hill. As a matter of fact, he didn't suffer any physical injury on the field.
Diekman has ulcerative colitis, a chronic disease that affects the large intestine and can lead to severe pain and abdominal cramps. Ulcerative colitis and Crohn's disease are two of the main illnesses that make up inflammatory bowel disease (IBD), which affects more than 1.6 million people in the United States.
No player in the history of Major League Baseball has undergone the procedures Diekman has gone through and returned to action -- until now.
At 10 years old, Diekman knew he didn't often feel like a lot of the other kids around him in Wymore, Nebraska. He continually experienced painful stomach cramps, frequent trips to the bathroom and general fatigue. He knew something was wrong. Initially, doctors thought he might have a case of water poisoning, but after things didn't improve, he was eventually diagnosed with ulcerative colitis.
At first, he was given medications like "souped-up Ibuprofen" to help ease the pain from the inflammation and sores within his colon. After a few years, doctors took a more focused approach.
"I had a PICC [peripherally inserted central catheter] in my arm when I was like 13 or 14, just like where I have an IV," Diekman said of his treatment. "We did that for two or three weeks."
Dealing with weight loss and abdominal cramps and consistent diarrhea isn't an ideal situation for anyone -- let alone a middle-school child, especially one involved in sports. In short, it can be quite isolating and awkward.
"I know as a kid and growing up with it, it's pretty embarrassing to talk about," he said. "The whole GI tract in general, to talk about poop as a kid, you feel like you might get made fun of."
Eventually the disease started to quiet down in high school, and he excelled on the diamond. He enrolled at Doane College before deciding to transfer to Cloud County Community College in Kansas for his sophomore year. As a 6-foot-4 lefty with a fastball that sat in the mid-to-low 90s, Diekman was beginning to get noticed. With a scholarship offer from the University of Nebraska on the table, he instead went professional after the Phillies selected him in the 30th round of the 2007 Draft.
But as Diekman soon learned, IBD comes with both unsavory symptoms and plenty of unpredictability. The stresses and anxieties of competing at a higher level built up. There were days when he felt on top of his game, and others when it was a struggle to get out of bed in the morning.
"I don't remember it flaring up much again until I got to pro ball," he said. "It was like every other year that I'd have a flare-up."
Though doctors prescribe anti-inflammatories, biologics and other medications that can lessen the pain or help put active disease into remission, there's currently no cure for IBD. What makes it even tougher from a medical standpoint, as Dr. Kostas Sideridis -- a gastroenterologist affiliated with Northwell Health -- knows, what might work for one patient might produce no positive results for another.
"The hardest part about treating IBD is that every person is different," he said. "There are people who have one Crohn's flare in their life and we never see them again, so we don't know what the natural history of the disease is. Some people show up with mild, moderate and severe forms the disease."
Even with the ups and downs and constant unknowns, Diekman persisted and put together a strong first impression in the Minor Leagues, posting a 2.72 ERA in 13 appearances (10 starts) between the Rookie-level Gulf Coast League and Class A Short Season New York-Penn League.
But in his first full season with Class A Lakewood in 2008, Diekman labored with a 5.42 ERA in 19 starts. A year later, though, he began his transition to a full-time reliever and excelled. Moving up through the Phillies' system, Diekman got the call to The Show in 2012, carrying a 3.95 ERA in his first 27 1/3 innings. After spending most of the first half of 2013 with Triple-A Lehigh Valley, he came back the big leagues in June and has stuck ever since, building his reputation as a valuable late-inning arm.
In need of pitching help at the non-waiver trade deadline in 2015, the Rangers acquired Diekman and Cole Hamels in a deal that sent then-No. 5 Texas prospect Nick Williams along with five others to Philadelphia. Diekman has proved his reliability since the trade, potsting a 2.93 ERA while fanning 81 batters in 76 2/3 innings. To those unaware, his success on the field might have obscured the extra work he had to put in off of it to remain in game shape.
"My job is to be able to pitch every day, so for three or four hours a day, I completely zone out," Diekman said. "If I used to go to the bathroom like eight times during the game, that's just what I did. The second I got back on the mound, I didn't even think about it -- it was the last thing on my mind."
Diekman's felt pain before, but something about last November felt different. After results came back from a colonoscopy in December, doctors suggested that he undergo J-pouch surgery, a multi-step procedure that would remove his diseased colon.
In the back of his mind, Diekman always knew this could happen, but now he was facing the gravity of the situation. There was the option of switching to a new biologic medication, but doctors believed at this point there'd be no "miracle one." The surgeries would keep him healthy and essentially symptom-free, but he'd miss most of the 2017 season. So Diekman relayed the news back to the Rangers, who were more than supportive in the situation.
"They were like, 'If I had a son and he needed to get this done, then you should get this done right now,'" Diekman recalls. "'The longevity of life is more important than your career right now. You want to live a fruitful, healthy life beyond this.' Once I heard that, it put me at ease a little bit more."
So it was decided -- in January, Diekman would undergo the first of three surgeries at the Mayo Clinic in Minnesota. He underwent pre-surgical tests and didn't eat for a full day before the operation. On Jan. 25, Diekman "felt like a skeleton" and went under the knife. He woke up with an ileostomy, an external stoma in his abdomen that released waste into a plastic pouch.
"You go into surgery and you feel pretty good," he said. "And then six hours later you have a bag connected to yourself. And you're like, 'Alright, this is the new normal. I guess we'll figure it out from here.'"
All the while, his fiancée, Amanda Soltero, stayed with him in the hospital, helped him get to appointments and was someone to rely on in tough times, especially after he had the ileostomy, which itself can be embarrassing.
"To me it wasn't gross or weird or whatever," she said. "To me, this was saving his life. So whatever that took, I was down for it. Even if he had to keep it for the rest of his life, as long as he could be around for our kids someday, sign me up."
One day after the surgery, Diekman got to eat for the first time. The small meal felt like a feast.
"When he could eat, I said, 'Five bites, that's it,'" Soltero said. "So I think I recorded him eating his five bites of mashed potatoes and he was just beside himself over it. Every meal was a treat after that."
For the next couple months, it was mashed potatoes and whatever else Diekman wanted to eat -- anything was an option because the pain was down and his appetite was skyrocketing. He even got to catch some Rangers games, albeit watching from a different perspective than usual.
"It's weird because as a player you watch baseball games and you see everything," Diekman said. "But on the DL, you get to critique everything with a microscope with all of the games. So in that sense it's also helped me out."
In early April, he went for another round of surgeries, including the one that would create the actual J-pouch reservoir in his body. Two months later, the external stoma was closed, meaning he didn't need the ostomy bag anymore. While this might have been the most painful of the operations, it quickly produced positive results.
"The whole GI tract still needs to fully heal -- they say it takes six months to a year to really feel everything working the way it should," Diekman said. "But I'm two months out and I feel better than I did the previous 10 years, which is great."
Whether Diekman was in pre-op, post-op or recovering at home, he and Soltero have made it a goal to be as transparent as possible with his illness. The two have shared plenty of pictures and videos on social media that have essentially chronicled the whole process this year.
Diekman wants others fighting the diseases to know they have a someone who understands what they're going through.
"I've seen a little boy, he's about 7 or 8 and he goes to school here. He has an ostomy and he has it forever now," Diekman said. "We invited him to a game and he rarely ever showed his bag. But we brought him to a game, we took him on the field after the game. We ran the bases with him and then I asked him if I could take a picture with his bag, and he was like, 'Yeah, it's no problem.' And that was like the first time he showed a stranger his bag.
"A couple of weeks later, we went to school with him for his fun and field day. All of the kids were super supportive and wanted to ask him and me questions about it. Now he feels a lot better about this, which is the reason why we wanted to start all of this in the first place."
"A lot of people don't talk about living with these diseases," said Rebecca Kaplan, public affairs and social media manager for the Crohn's and Colitis Foundation. "And because of that, a lot of people don't know anything about them and how serious and debilitating they can be. When people like Jake and Amanda, who have a broader appeal, start talking about the specifics it really raises awareness of how serious and debilitating these diseases are. But it also combats the stigma of the diseases that has a large focus in the bathroom."
On many of their social media posts, you can spot Diekman and Soltero sporting shirts with the motto "Gut It Out" emblazoned across the chest. They've teamed up with Athletes Brand and started selling the shirts to raise money and awareness about IBD. This August, Diekman and Soltero took it a step further by creating the "Gut It Out Foundation" in hopes that one day no one will have to suffer from IBD.
"We feel like we can make a difference. We feel like we can put it toward what we want," Diekman said. "If that's research or sending kids to a camp somewhere -- I mean anything. I think we've pinpointed things in the IBD community as a whole. Hopefully one day we can find a cure so they can get rid of this forever."
A few days into a work trip in Las Vegas, Soltero received a text message from Diekman about his long-awaited rehab assignment. It would begin Aug. 17.
"It said, 'OK, it's going to start Thursday,' and I was supposed to get back Thursday morning anyway," she said. "Then I had a couple of days there to think, 'Thursday, Thursday, Thursday.'"
When Thursday morning rolled around, Soltero could hardly contain her nervousness. This had been a day she and her fiancée had been waiting for, and it was here. She took a flight home to Dallas that morning and quickly headed to Frisco with Jake's father, Paul, to see him pitch with the RoughRiders against Arkansas.
With the game scoreless heading into the fifth inning, Frisco manager Joe Mikulik put in the call to the bullpen -- Diekman would be coming in. He hummed two pitches out of the zone to leadoff man Tyler Marlette, but then induced a ground out. With the adrenaline flowing, Diekman fanned Steven Baron and Willie Argo to end a perfect frame. While he was on the mound, Soltero "had a calm come over" her, but as Diekman worked his way toward the dugout, all of the emotions came over her at once.
"I didn't cry or anything until the end, when he ran off," she said. "In the moment, it's not quite hitting you what's going on -- you're just watching and waiting. And then when it was over I just felt like a weight was lifted off. I started crying after that. He felt amazing afterward."
In the next half, Frisco jumped ahead with two runs and held onto the lead for good, meaning Diekman earned the win. In a year where little victories meant the world, this one will forever be engrained in a box score as well as the memories of Diekman and Soltero.
"People just don't do that -- that just doesn't happen," Soltero said. "For him to be in a position where they trusted him to go out there and go out and play, I didn't care what happened. The fact that he was able to go out there so quickly when it just doesn't happen for most people, it was enough for me."
He cruised through his next five rehab assignments between Frisco and Triple-A Round Rock, yielding just one run on three hits over 6 1/3 innings.
On Aug. 31, Diekman knew there was a good chance he'd hear his name called up the following day when Major League rosters expanded to 40 players.
"Hopefully I get thrown into the fire and get in Friday or Saturday, he said. "It's been a very, very long road."
Thrown in he was. On Sept. 1, Diekman was not only active but called upon in the seventh inning, tossing a scoreless frame against the Angels to earn his first hold of the season. One day later, he was back on the mound again and put up another zero.
Back on the field and with a clean bill of health, Diekman has newfound stability in his life. Now, they have another important date planned and circled.
"It's given me time to evaluate the important things in life," Diekman said. "My fiancée, four months from [Aug. 31], we're getting married. She's amazing. She's been by my side every step of the way. She's been my rock through this entire thing and I can't thank her enough."