Hot Fantasy Prospects To Watch For Week 13

June 23, 2021

Michael Grennell's fantasy baseball prospects who are risers and sleepers entering Week 13 of the MLB season. Keep an eye on these rookies and call-ups for fantasy on the waiver wire.

Well the big prospect domino has finally fallen. Wander Franco is getting called up and is expected to make his major league debut today. I got to admit, I was not expecting Franco to be up this early. Between reports earlier this season that the Rays intended to take things slow with him, plus how Vidal Brujan looked early on, I thought for sure we wouldn't see Franco before the All-Star break. In last week's column, I mentioned how wrong I was when Juan Soto came up in 2018 and I've got a sneaking suspicion that I'm going to be proven very wrong once again with Franco.

Enough about Franco. You can check out other content from the RotoBaller staff — such as Marc Hulet's Top 50 Fantasy Baseball Prospects column or Kev Mahserejian and James Anderson's latest Fantasy Rookies and Prospects podcast episode — to hear more about Franco and his potential. We're going to keep things focused on guys still in the minors. We've got two pitchers and two infielders to look at who have been having some hot streaks recently, and the first guy we'll get to is the top middle infield prospect in the minors now that Franco is going to The Show.

Let's not waste any more time and get right to it.

Bobby Witt Jr. - SS, Kansas City Royals

Level: Double-A
2021 stats: 38 G, .280/.352/.561, 11 HR, 11 SB, 24 RBI, 28 R

The No. 2 overall pick in the 2019 draft, Witt has not let the canceled 2020 season slow him down one bit. Except for triples, Witt has already surpassed all of his marks from 2019 with the AZL Royals, where he slashed .262/.317/.354 with one home run and nine steals over 27 games. He's turned things up another notch in the month of June, where he is currently slashing .353/.413/.691 with four homers, five steals, 12 RBI and 12 runs scored over 17 games. We're dealing with small sample sizes here obviously, but Witt has seen his strikeout rate climb up a little bit from 19.4 percent in 2019 to 25.6 percent this year. However, he has also improved the walk rate from 7.2 percent to 9.7 percent.

I want to say that we won't see Witt get called up until late this year, but given my track record with Soto and Franco, maybe I should be more high on Witt making an impact in 2021? On the other hand, I think there are a couple of solid points against him reaching the majors before September. First, he has a grand total of 75 games of professional baseball under his belt. And second — and probably more importantly — the Royals are likely not going to be in the playoff hunt this year.

As such, there's little motivation for Kansas City to rush Witt through the system. I think it's far more likely we'll see him competing for a starting job out of Spring Training in 2022. However, if you have a deep enough bench in a redraft league, it couldn't hurt to stash him just in case, as he could be a high end power-speed option in the middle infield.

Penn Murfee - SP, Seattle Mariners

Level: Double-A
2021 stats: 7 GS, 37.1 IP, 3-1, 4.10 ERA, 1.393 WHIP, 45 K

Despite one downside I'll mention later, I have to talk about Murfee this week after the dominant performance in his last start. Going up against the Tulsa Drillers, Murfee allowed three hits and two walks while striking out 11 in a complete game shutout. That is the latest in what has been three straight solid outings, where he has combined to go 2-0 with a 1.80 ERA and 23 strikeouts in 20 innings of work. It's been a significant turnaround for Murfee, who struggled in his first four starts of the year where he posted a 6.75 ERA and 1.904 WHIP over 17 1/3 innings, but still managed to record 22 strikeouts over that stretch.

Now the bad news: Murfee is old for the league. At 27 years old, he is over two years older than the weighted average age of pitchers at Double-A. He's still putting up good numbers, but managers should take them with a grain of salt as he's pitching against guys who haven't had as much development.

That being said, I think his age makes it likely that we'll see him get called up to Seattle sooner than later. Before he joins Seattle, he'll almost certainly get some time pitching at Triple-A. Fantasy managers should keep an eye on his performances. If he does reach Seattle this year, he looks to be a decent streaming option in deeper formats right out of the gate.

Sherten Apostel - 1B/3B, Texas Rangers

Level: Double-A
2021 stats: 31 G, .264/.352/.509, 6 HR, 18 RBI, 14 R

For the second week in a row, I'm highlighting a guy that I got to watch in person while working in the minor leagues. Apostel showed some pop when I saw him with the Bristol Pirates in 2018, and this year at Double-A the power is at an all-time high for him. After a slow start to the season where he slashed .216/.333/.353 in May, Apostel has turned things around this month as he's slashing .309/.371/.655 with five homers, 11 RBI and 10 runs scored over 16 games. While the strikeout rate is up a bit from his 2019 mark of 22.3 percent, he has also improved his walk rate from 10.7 percent to 12.3 percent.

He struggled in his first taste of the majors last season where he went 2-for-20 with one double, one walk, and nine strikeouts over seven games. However, he was only 21 years old at the time. Now as a 22 year old, he's putting up these good numbers while being just over two years younger than the average weighted age at Double-A. Based on those struggles in limited playing time last season, the Rangers may want to keep him in the minors a little bit longer to make sure he's got his swing down.

However, if injuries strike in the infield, I could see Apostel getting called up sooner than later. I will say that right now any value he would have once he's called up will be limited to deeper mixed and AL-only formats, but if he gets off to a hot start and gets regular playing time, then managers in shallower formats will want to take a close look at him.

Reid Detmers - SP, Los Angeles Angels

Level: Double-A
2021 stats: 8 GS, 35 IP, 2-2, 3.34 ERA, 1.229 WHIP, 60 K

Last but not least, let's talk about the No. 10 overall pick in last year's draft. It took him a few starts to get his legs under him, but over his last three starts in the month of June, Detmers is 2-0 with a 2.40 ERA and a 47.6 percent strikeout rate in that span. He has recorded double-digit strikeouts in three of his last five starts, and in his latest outing against the Biloxi Shuckers, he allowed two runs on three hits and two walks while striking out a career-high 14 over six innings of work.

Without question, Detmers is the top pitching prospect in the Angels' system right now. He is looking great as a 21-year-old making his pro debut at Double-A. That being said, he only has 35 innings of pro ball under his belt at this point. He's the least likely to see any time in the majors this season, but I won't say it's impossible.

If the Angels can turn things around and find themselves in the midst of the playoff hunt, I can see Detmers getting called up as a late season spot starter, or a guy to bolster the bullpen in the playoffs. Either way, managers should start keeping a close eye on Detmers as he's not too far off from reaching the Angels.

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