Starting pitcher is without a doubt the deepest position in fantasy baseball, but at a certain point, it becomes a pool of mediocrity. Finding those lesser-known starters who can rise above the mediocrity is a major key to fantasy success. Each of these five pitchers can be had late in drafts, and have the potential to break out and make a solid impact on fantasy teams. Whether it's in deep mixed leagues or AL-Only leagues, these (mostly) young arms are worth some consideration.

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Deep Sleepers: American League Starting Pitchers

Andrew Heaney, Los Angeles Angels

After a rocky first go-round in the majors, Heaney found his form in 2015, appearing in 18 games and posting a 3.49 ERA for the Angels. I wrote about Heaney almost two years ago, claiming he was a can't-miss prospect, and I maintain that mentality. He hasn't quite reached his full potential, but he has shown flashes of brilliance. Through his first seven starts in 2015, his ERA stood at 1.97, and it didn't reach the 3.00 mark until a horrid, eight-run outing in late August. If you ignore that one unfortunate evening against the Blue Jays smack in the middle of a historic offensive stretch (54 runs in five games), Heaney's 2015 ERA would have been 2.90, which would have placed him fourth in the American League.

His 6.64 strikeout rate is unappealing, but his 8.50 rate in Triple-A indicates that he could induce more swings and misses going forward to go along with his above-average walk rate. The Angels have a lot of mediocrity towards the back-end of the rotation, and Heaney should have no problem rising above the pack. If he slips to the end of a deep mixed-league draft, he could be worth grabbing.

Daniel Norris, Detroit Tigers

Following the trade that sent Norris to the Tigers and  David Price to the Blue Jays, Norris turned it up a notch. Over eight starts the rest of the way, he posted a 3.68 ERA with an incredible 4.7% walk rate (11.7% in Toronto). Opposing batters hit just .213 against him over that span, he induced more ground balls while allowing fewer line drives and fly balls, and only 24.6% of balls hit off him were hit hard. Additionally, his scarily low 59.4% LOB% should level out, and he could prevent even more runners from crossing the plate.

Back in 2013, the Orioles were anticipating a dominant 1-2 punch of Dylan Bundy and Kevin Gausman in the near future. Yet here they are, three years later, without an ace. While Bundy hasn't even scratched the surface of the big leagues, Gausman has at least been a serviceable Major League starter over the last two years. He posted an ERA of 3.57 in 2014, but that number dropped to 4.25 in 2015. His improved strikeout rate (21.9%, up from 18.5%) and walk rate (6.2%) were nice to see, though, and he lowered his batting average against from .254 to .248.

He left roughly the same amount of runners on base (72.3%), and his 27.4% Hard% was actually lower than that of 2014. His fastball gained velocity and was very effective, and he saw improvements with his splitter. Overall, while his ERA and FIP were sub-par, his 3.80 xFIP was around the league average and his 3.68 SIERA was firmly above average. The only real negative for Gausman was his HR/FB, which jumped from a stellar 5.8% in 2014 -- the seventh best among the 149 starters with at least 100 IP -- to an ugly 13.4% in 2015. Yes, Camden Yards is considered to be a hitter-friendly ballpark, but that's a drastic change for a pitcher who otherwise made positive strides.

Gausman spent some time as a reliever last year, but should be cemented into the Orioles' rotation for 2016. If he can stay healthy and find a way to keep his fly balls from clearing the fences, the 25-year-old can be in for a major breakout season.

Kris Medlen, Kansas City Royals

Medlen is far removed from his glory days in Atlanta -- a 1.57 ERA, a 0.91 WHIP and 120 strikeouts in 138 innings as a starter/reliever hybrid in 2012 -- but he had an impressive bounce-back season in a similar role for the Royals in 2015. In 58.1 innings, he managed a 4.01 ERA, a 1.27 WHIP and 40 punch-outs. Medlen allowed 22 earned runs over eight starts, with 13 of those runs coming in two horrid outings-- understandable for a guy coming off of his second Tommy John surgery.

He's not the safest pick, given his injury history and lack of sustained success, but he still possesses the talent that made him so exciting just a few years ago. His fastball had as much velocity last year (91 mph) as it had when he came up., and he threw it for a strike 54.7% of the time. As long as he remains healthy and in the starting rotation, he holds value as a sleeper in deep leagues.

Blake Snell, Tampa Bay Rays

Snell has never thrown a pitch in the big leagues, but has an incredible minor league track record. He followed up a strong 2014 campaign (3.20 ERA in 115.1 IP between High-A and Single--A) with a historical 2015 stat line. His 1.41 ERA led all minor league pitchers, and was the lowest minor league ERA in a decade. The Rays' No. 1 prospect has improved his command throughout his time in the minors, lowering his walk rate from 16.3% in 2013 to 10.2% in 2015. He also added a spectacular 31.3% strikeout rate last year.

In the event of an injury or trade, the Major League-ready Snell would have the opportunity to jump into the Rays' rotation, and given his talent, his first stint in the majors could be permanent. In dynasty or keeper leagues, as well as deep AL-Only leagues, Snell is worth consideration as a sleeper.

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