Prospect Roundup: Games of Aug. 30

Theme of the day

Gearing up for the Fall League:Arizona Fall League rosters were announced Thursday afternoon with top overall prospect Vladimir Guerrero Jr. headlining the batch of Minor Leaguers headed to the Grand Canyon State. Shortly afterward, two players named on those rosters showed why this year's AFL could be so exciting. No. 2 Blue Jays prospectBo Bichette, who will join Guerrero on the Surprise roster, posted his fifth straight multi-hit game for Double-A New Hampshire. One level lower, No. 3 White Sox prospect and future Glendale Desert Dog Luis Robert doubled twice on a three-hit, four-run night for Class A Advanced Winston-Salem.

Who stayed hot

Mariners 1B Evan White, Class A Advanced Modesto: 3-for-5, 3 2B, 2 RBI, 2 R, 2 K -- The Mariners' No. 2 prospect kept his hot August going with three two-baggers -- the first time he's collected three extra-base hits in a pro game. White is batting .375/.462/.727 with five homers, three triples, 10 doubles and 25 RBIs in 23 games this month, pushing his season line to .299/.371/.458 in 116 games. Of the 44 extra-base hits he's notched this season, 40.1 percent have come in August. More on White's late-summer surge in Wednesday's Toolshed.

Who needed this one

Orioles RHP Michael Baumann, Class A Advanced Frederick: 7 IP, 2 H, 0 R, 1 BB, 5 K, 82 pitches, 58 strikes -- The Orioles' No. 21 prospect began the day with a 4.20 ERA through 16 starts with Frederick after having allowed 13 earned runs over 13 1/3 innings in his previous three outings. He brought it down to 3.88 with his longest outing since tossing seven frames in his Carolina League debut on May 20. Baumann was efficient, needing only 82 pitches to get through his seven frames, thanks to improved command. The 22-year-old has walked 10.3 percent of the Class A Advanced batters he's faced, but issued just one walk to the 22 P-Nats he saw Thursday. Though his fastball and slider earn above-average grades, Baumann has struggled to get whiffs with Frederick, having struck out only 59 in 92 2/3 innings. With the Keys out of the playoff picture, this was likely Baumann's last start of 2018. More on that in Chris Bumbaca's story here.

The unexpected

A's SS Richie Martin, Double-A Midland: 4-for-4, 3B, 2 2B, RBI, R, SB, CS -- The A's No. 12 prospect has surged lately, hitting three homers over five games between Aug. 23-28, but took things to a whole new level with his performance against San Antonio. This was Martin's second four-hit game of the season, and his three extra-base hits also marked a new career high. A career .254 hitter with a .361 slugging percentage in the Minors, the 2015 first-rounder is known much more for his above-average speed and his plus defensive ability at short and second base. He's been solid at the plate this year and enters the final four games of the regular season with a .293/.362/.426 line and 116 wRC+ with Midland.

Best matchup

Triston McKenzie vs. Yusniel Díaz: Usually, hitters solve pitchers after seeing them multiple times over the course of a game. But this Eastern League matchup between MLB.com's No. 36 (McKenzie) and No. 54 (Diaz) prospects saw the opposite. Diaz singled to left off McKenzie in the second inning, but the Akron right-hander got the Bowie outfielder to pop out to short in the fourth and strike out looking in the sixth. Diaz is 2-for-5 with a walk and two strikeouts against McKenzie. More on the top Indians prospect's six scoreless frames Thursday in Vincent Lara-Cinisomo's story here.

Who strengthened their promotion case

Yankees LHP Justus Sheffield, Triple-A Scranton/Wilkes-Barre: 1 IP, 0 H, 0 R, 0 BB, 0 K, 12 pitches, six strikes -- The Yankees moved their top prospect to a relief role on Aug. 21 in anticipation of calling him up to the big league bullpen in September, only to see middling results. Sheffield yielded an earned run over two innings in each of his first two relief appearances. Against Syracuse, however, he had no issues getting three quick outs on 12 pitches in a spotless eighth inning in Scranton/Wilkes-Barre's 3-2 win. Sure, it's just one frame, but if the Yanks needed good news before making Sheffield's promotion official, they got it. The 22-year-old left-hander has two plus pitches in his fastball and slider and an above-average changeup, all of which will work in short stints in the big leagues. He'll be back in the rotation discussion next spring.