"I was as hot as anyone can be," said the personable 24-year-old, standing in the Western Division clubhouse before the Eastern League All-Star Game in Reading, Pa.
The former Xavier University standout was a perfect 3-0 with an ERA of 0.76 in April and then went 3-1, 2.76 in May. But baseball is game of highs and lows, and that fast start caught up with him. He was 1-4 with an ERA of 6.27 in June, allowing 45 hits in 33 innings.
"I let it get to me a little bit," Rosenbaum admits of the rough patch. "I didn't think I would get hit that hard."
Rosenbaum, who insists he's totally healthy, relies on his control and change of speeds to keep batters off-balance.
"He's in that adjustment phase," said Doug Harris, the director of player development for the Nationals. "We're confident he'll be fine. It's really trusting yourself and executing. Trust what got you there -- that's the biggest thing. The last few [outings] have been a little more crisp."
That mini-resurgence continued Sunday as Rosenbaum allowed just one run in six innings, although he gave up nine hits and did not earn a decision in an 8-7 loss at home to Richmond. He walked just one batter and had five strikeouts while lowering his ERA to 3.44 in 19 starts. In 120 1/3 innings this season, the 22nd-round pick in 2008 has allowed 121 hits and just 26 walks with 76 strikeouts.
Alex Smith, a Maryland-based scout who helped sign Rosenbaum, recalled what he saw in the hurler prior to his pro career.
"I saw an above-average fastball and above-average control," he said. "I saw a left-hander with arm strength who could spin a breaking ball and had a feel for pitching. He should have never fallen to the round he did."
Smith, now a national cross-checker for Seattle, has remained in touch with Rosenbaum's family.
"He is a great kid from a super family," Smith said.
The No. 19 prospect in the Washington system, Rosenbaum said he had some bad luck in June and was encouraged by his two July starts prior to the All-Star break.
"Dan prepares extremely well, and he is very meticulous in everything he does," Harris said.
So is it possible the cerebral lefty might have been thinking too much during a rough June?
"I think that's fair," said Harris, a former Minor League pitcher with Baltimore and Kansas City. "Sometimes it is a blessing to be blessed with ignorance in this game."
Hey now, I'm an All-Star: Binghamton's Eric Campbell, whose walk-off single won the Eastern League All-Star Game, 5-4, on Wednesday for the Eastern Division, had two hits and an RBI on Sunday to lift his average to .353 for the month of July. He hit .269 in April but through Sunday was hitting .325 with six homers, 17 doubles and 38 RBIs. The Norwich, Conn., native was an eighth-round pick of the Mets in 2008 out of Boston College.
Cooling off: New Hampshire first baseman Mike McDade had four hits in four at-bats in the Eastern League All-Star game but is struggling in regular-season play. He was 2-for-17 against Portland in five games from Thursday through Sunday and was hitting .171 in his last 10 games. A left-handed hitter, McDade was hitting .195 against lefties and .315 against right-handers.
A wild one: Richmond scored three runs in the top of the ninth inning Sunday and held on for an 8-7 win when Harrisburg scored twice in the bottom half. Juan Perez had four hits in four at-bats for Richmond. Drew Storen, on a Major League rehab assignment with the Nationals, retired two batters in the seventh but gave up three hits, a walk and four earned runs. Infielder Zach Walters, called up from Potomac earlier this season, had three hits for Harrisburg to improve to .344 in 25 games with the Senators.