Hot Prospects To Watch - Kelenic Cruising, McKay Dominating, Singer Soaring

We've had the pleasure of seeing two more high-profile prospects make their big league debuts in the past week, with Blue Jays second baseman Cavan Biggio debuting last Friday and Mitch Keller making his first major league start on Tuesday night against the Reds in the second game of a doubleheader.

Biggio, while not ranked as a top-100 prospect by MLB Pipeline, was considered the team's No. 9 prospect. The son of former big leaguer Craig Biggio, Cavan has gotten off to a nice start in his three games, with all three hits and his first career home run coming on Sunday against the Padres. He could be here to stay.

Keller, the Bucs top prospect and No. 21 in all of baseball, didn't have the kind of debut he was hoping for. The 23-year-old right-hander allowed seven hits (a grand slam) and six earned runs while walking two and striking out seven in four innings. Keller could be sent right back down to the minors, but he should be back again in 2019 if so and has tremendous upside in all formats.

M's Have A Good One In Kelenic

Jarred Kelenic - OF, Seattle Mariners

The former sixth overall pick of last year's draft by the Mets, Kelenic has hit .304/.394/.558 with nine home runs, 25 RBI, 30 runs scored and seven steals in 47 games for Single-A West Virginia. He has 25 walks and 45 strikeouts and has been caught stealing four times.

He was part of the return for the Mariners when they sent closer Edwin Diaz and All-Star second baseman Robinson Cano to the Mets in the offseason. Just 19 years old, Kelenic was one of the best pure overall bats in his draft class, and he's showing why in his first full professional season.

The left-handed hitter has an outstanding feel for hitting with an advanced approach at the dish and regularly barrels up the baseball. The team's No. 2 prospect and No. 42 overall should develop above-average power at the next level as he matures. With above-average speed as well, Kelenic's maturity and work ethic should make him a starting outfielder in Seattle in a few seasons.

There's still plenty of development for him in the Mariners system, but Kelenic has the defensive prowess to play anywhere in the outfield long term.

McKay's Arm Is His Ticket To The Bigs

Brendan McKay - SP/DH, Tampa Bay Rays

Touted as a two-way star when the Rays drafted him fourth overall in 2017 out of Louisville, McKay's arm is much more advanced than his bat at this point. He's hitting only .159 (13-for-82) with no homers, nine RBI, seven walks and 28 strikeouts for Double-A Montgomery and Triple-A Durham in 2019.

On the mound it's a different story entirely. The 23-year-old is 3-0 with a 1.30 ERA, 0.82 WHIP, 62 strikeouts and only nine walks in eight outings (seven starts) over 41 2/3 innings for Montgomery. He's allowed two home runs on the season.

The left-handed hurler uses a mid-90s fastball with excellent command and also sports an above-average curveball and cutter. McKay just has a feel for pitching and consistently keeps hitters off balance with his fine command of his arsenal. He's shown advanced patience as a hitter, but he hasn't had the impact with his lumber that the Rays initially had hoped for.

Tampa will strictly use their No. 3 prospect (No. 29 overall per MLB Pipeline) at designated hitter and will likely continue to limit his opportunities with the bat to avoid injuries. It doesn't mean he won't hit at all when he makes it to the majors, but he's not going to be the next Shohei Ohtani.

Singer Slinging Shutouts

Brady Singer - SP, Kansas City Royals

The Royals top prospect and No. 50 overall, Singer turned in his third straight scoreless start by giving up four hits while striking out four and walking two for High-A Wilmington on Monday. As a result, Singer was promoted to Double-A Northwest Arkansas after the game.

The 22-year-old right-hander is now 5-2 on the season and hasn't allowed an earned run in his last 22 innings. In five May starts, he's gone 3-0 with a 0.90 ERA, 29 strikeouts, five walks and a 1.00 WHIP. The 18th overall pick out of the University of Florida last year is the ultimate competitor when he gets on the bump, and he's been keeping his fastball and slider down in the zone this season.

Singer's fastball and slider are both plus pitches, and he throws a two-seamer with sink and a four-seamer that has late life. He's developing a changeup as a third pitch as a professional, but his slider has the stuff to be a true out pitch for him. Singer has excellent command and control, which should give him a pretty high floor as he rises quickly through KC's system.

It'd be a surprise if Singer is in the big leagues in 2019, but he has the stuff and makeup to compete for a starting rotation spot in spring training next year.

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