Last week I identified five underrated hitters to watch and be ready to grab off your fantasy baseball league waiver wire, and this week, starting pitchers. Here are four, perhaps best started or benched depending on their matchup, but the upside potential is there, plus a deeper look at the St. Louis Cardinals’ rotation.

RHP Luis Castillo, CIN

Heading into 2018 on the heels of an impressive 2017 debut, the 25-year-old Castillo isn’t necessarily locked into a rotation spot for the Cincinnati Reds – but he’s got a silly array of pitches (fastball, slider, sinker, changeup) and is fully capable of going 6 innings a start – his average last year. He’s been throwing his changeup as an out pitch, getting a 42% swinging strike rate on the pitch, and he’s generating more ground balls with his sinker. He’s struggled considerably in his first two outings, but there’s more upside than downside considering his stuff. He is due for more strikeouts (9.87 K/9 in 2017) and better overall results as the luck-based metrics (BABIP & LOB%) normalize.

RHP Reynaldo Lopez, CWS

While it’s unrealistic to think Lopez will maintain his currently low ERA, the lofty walk rate should drop and he’ll start making a name for himself with that nasty breaking stuff (curveball and slider – the latter a developing out pitch for the 24-year-old). The White Sox offense has shown some improvement so he should be getting more run support, and if he can stay healthy in 2018, there’s no reason to think he can’t be a viable starter with some upside in standard leagues. So far, he’s been excellent in two starts.

RHP Mike Foltynewicz, ATL

“Folty” as I like to call him when building my daily fantasy (DFS) lineups, occasionally sprinkling him in as an SP2 in favorable matchups, is a much better pitcher versus right-handed batters – as is mostly the case for right-handed pitchers. For this reason, it’s always a risk to run him out there against potent lineups with a bunch of lefties. He’s also a much better pitcher at home, which is a bit odd considering the cozy dimensions of SunTrust Park for LHB. But some of his metrics and burgeoning command tell us 2018 could be a breakout year as he develops his changeup – a pitch that’s served him well through his first couple starts. The changeup makes a nice fourth pitch to go along with his slider and curve, both plus pitches for him in an unremarkable 2017.

RHP Ben Lively, PHI

At 26 years old and in just his second season in the big leagues, Lively isn’t a name that got a lot of play during most fantasy drafts this winter, and the pitcher isn’t going to blow anybody away with electric stuff – as his career SwStr% is just 7.4% through 17 career starts and 100 IP. But Lively has a deceptive delivery similar to Yusmeiro Petit’s – and a pitch that former FanGraphs and current The Athletic baseball scribe Eno Sarris has dubbed “The Invisiball”. Lively has been knocked around a bit in his first two starts, but there’s some room for growth as a back-end rotation man and fantasy asset in deeper NL-only leagues.

Rotation Spotlight, St. Louis Cardinals
RHP Miles Mikolas – RHP Luke Weaver – RHP Jack Flaherty

Mikolas, who spent the past few seasons in Japan, has shown better command and a much better baseline for MLB success in his first two outings – not walking a batter through 12 innings and off to a 1-0 record despite a bloated 6.00 ERA. The metrics say he’ll eventually post an ERA between 4.00 and 4.50, and strike out a lot more batters than he did before his trip East.

Mikolas isn’t the only Cards starter who’s on the fantasy fringe. 24-year-old Luke Weaver and 22-year-old Jack Flaherty, who’ve both made starts in 2018, are also high-upside options. Flaherty got the nod after an injury to Adam Wainwright (always a possibility given the mileage on his arm) and struck out nine batters through 5.0 innings in his debut.

The more experienced (but still raw – just 20 career starts) Weaver has a more solid rotation spot, and has probably been snatched up in most fantasy formats. But Flaherty – if given the opportunity – and Mikolas (who’s a much better pitcher than when he was with San Diego and Texas) could perform at a similar level to Weaver in 2018 – at a much cheaper price tag.