Prospect Roundup: Games of May 9

Theme of the day

Tommy John at both ends: Elbow injuries are a fact of life for professional pitchers. First, there's the terror of the news that Red Sox No. 2 prospect Jay Groome will undergo the elbow surgery next week. The 19-year-old left-hander's career has already been ravaged by injuries that have limited him to 62 innings since being selected in the first round of the 2016 Draft. Good things can come after the Tommy John rehab process, however. Making his first rehab start with Class A Advanced Palm Beach, No. 18 overall prospect Alex Reyes showed that his velocity is all the way back when he hit 99 mph on the radar gun. Losing Groome for a year-plus is deeply unfortunate, but Reyes, at least in one start, demonstrated that all is not lost.

Who stayed hot

Reds RHP Tony Santillan, Class A Advanced Daytona: 8 IP, 4 H, 0 R, 1 BB, 2 K, 98 pitches, 68 strikeouts -- This matched the No. 4 Reds prospect's longest outing of his career and marked the sixth time in seven starts this season that he's allowed one run or fewer. The only qualified pitcher with a lower ERA in the Florida State League than Santillan's 1.28 is Bryse Wilson (0.34), who was promoted to Double-A Mississippi this week. Santillan, known for his plus-plus fastball and above-average slider and changeup, has consistently gotten whiffs with a 22.4 percent strikeout rate, but has lowered his walk rate from 10.5 percent in 2017 with Class A Dayton to just 5.9 percent this year.

Who needed this one

Nationals SS Carter Kieboom, Class A Advanced Potomac: 2-for-3, R, 2 BB -- Potomac manager Tripp Keister said on this week's Minor League Baseball podcast that he wasn't at all worried about Kieboom's slow start -- he was hitting .191 as late as May 2 -- adding that the No. 89 overall prospect just needed some balls to drop in. That has started to happen -- Kieboom now has hits in six straight games, going 9-for-22 (.409) to push his season line to .227/.342/.379. The 20-year-old has also found other ways to reach base. With two walks Wednesday, Kieboom has taken a free pass in six straight games and now ranks second in the Carolina League with 23 walks over 32 games.

The unexpected

Cubs C/1B Miguel Amaya, Class A South Bend: 2-for-4, HR, 3B, 2 RBI, 2 R, K -- The Cubs' No. 10 prospect surprised in two ways. First, his home run gives him a new career high of four, besting the three he hit over 58 games with Class A Short Season Eugene in 2017. Second, his triple was just the second of his career through 142 games. The 19-year-old backstop entered 2018 primarily known for his glove and arm but has struggled with the latter -- he's thrown out only two of 24 attempted base stealers. His .247/.311/.473 line is an improvement, however, making Amaya the most intriguing catching prospect in the Chicago system.

Best matchup

Mitch Keller vs. Austin Hays: This Double-A matchup between MLB.com's No. 15 and 37 overall prospects didn't catch Keller on a great day. The Pirates right-hander allowed six runs (four earned) on nine hits and three walks while fanning only one over 4 1/3 innings in Altoona's 8-2 loss to Bowie. Hays was not Keller's biggest problem of the afternoon, however. The O's outfielder struck out swinging in the first inning (though he reached on a wild third strike), collected an infield single in the third and flew out to center in the fourth. With Keller off his game, this could have been an opportunity for the right-handed slugger to get things going. Instead, he finished 1-for-6, dropping his season line to .224/.269/.400 through 30 games. 

Who strengthened their promotion case

Cardinals RHP Jack Flaherty, Triple-A Memphis: 6 2/3 IP, 6 H, 2 R, 2 ER, 0 BB, 13 K, 113 pitches, 77 strikes -- This was a Major League effort. Read more about it in Tyler Maun's story here. Flaherty has already made two big league starts this season and apart from walking four Pirates over five innings on April 28, showed that he belongs in The Show. The only thing keeping him in the Minors is a roster crunch. With a 2.27 ERA and 41 strikeouts in 31 2/3 innings at Triple-A, Flaherty has nothing left to prove in the Minors.

Others of note

Rockies 1B Chad Spanberger, Class A Asheville: 3-for-4, 2 HR, 2B, 6 RBI, 4 R, BB -- Playing home games at McCormick Field can be a godsend. The Rockies' No. 25 prospect plated six of the Tourists' 14 runs in his second career two-homer game. Six of his seven home runs this season have come at home, where his 1.294 OPS dwarfs his .587 mark on the road.
Royals 1B Nick Pratto, Class A Lexington: 3-for-4, HR, 4 RBI, R, K -- The Royals' 2017 first-rounder is adjusting well to his first full season, posting a .284/.333/.477 line with five homers in 28 games.
Tigers OF Daz Cameron, Class A Advanced Lakeland: 3-for-4, HR, 2 RBI, 2 R, BB, K -- The Tigers' No. 9 prospect, who hit 14 homers last season at Class A, went deep for the first time in 2018 in his 28th game of the season. Power has been tough to come by in the Florida State League for the 21-year-old, but he is batting .283 with a .369 OBP.
Dodgers RHP Dustin May, Class A Advanced Rancho Cucamonga: 5 IP, 6 H, 0 R, 1 BB, 9 K, 72 pitches, 48 strikes -- The Dodgers' No. 11 prospect strung together five zeros in his second start of the season after spending April in extended spring training. He's fanned 13 and walked two over 8 2/3 innings with the Quakes so far.