In fantasy parlance, the term "sleeper" is weirdly complicated. It requires context. A player can be a legitimate sleeper in one league and a sixth-round pick in another.

When we refer to anyone as a sleeper, all we're really saying is that the general perception of the player — based on their availability and average draft position — is out of sync with their clear potential to produce at a high level.

Your definition of "sleeper" is of course going to be heavily influenced by the size and competitiveness of your fantasy format. For example, if you play in a casual 8-team family league, then a sleeper is pretty much any player who doesn't regularly appear in State Farm commercials. If instead you play in a 20-team IDP dynasty league with a taxi squad and 10-round rookie draft, then there's really no such thing as a sleeper. Managers in your league are already scouting the rotational pass-rushers of the Mountain West. You will never encounter a fantasy article that mentions a player who isn't on your radar.

For our purposes here, we will define a sleeper as any player who A) has an ADP above 120.0 and is B) rostered in less than 60 percent of Yahoo leagues. So these guys are typically drafted outside the first 10 rounds, if they're selected at all. Each of them has a clear path to fantasy relevance, too.

You won't find industry favorites like Mike Gesicki, Hayden Hurst, Jonnu Smith or Noah Fant here, because those guys almost never go undrafted. All four are rostered in at least 80 percent of leagues. It's fair to consider them undervalued, but they are certainly not under-rostered. Today, we're scrolling a bit deeper in the tight end pool, looking for unappreciated upside.

Blake Jarwin, Dallas Cowboys

50 percent rostered, ADP 133.3

It feels like we've done all we possibly can to hype Jarwin — please see this piece and this piece — and yet he remains widely available to fantasy managers. He ranked eighth among all tight ends in yards per target last season (8.9), just ahead of Mark Andrews (8.7) and narrowly behind Travis Kelce (9.0). This year, he's headed for a huge leap in opportunities. Jason Witten and Randall Cobb both relocated in the offseason, leaving 166 targets up for grabs in Dallas. Jarwin is in line to receive a significant share of that workload. Last season, only four NFL tight ends were targeted 100 or more times; Jarwin is likely to reach that mark, assuming good health. He becomes an excellent pivot option if you fail to land an upper-tier TE in your draft.

Chris Herndon, New York Jets

47 percent rostered, ADP 138.0

Many of you will remember the buzz generated by Herndon last summer during camp and preseason. He appeared to be a preferred target for Sam Darnold, a good bet for a breakout campaign following a promising rookie season (39-502-4). He was suspended for the opening weeks of 2019 (DUI related), but he seemed like a lock to produce in October -- until the injuries hit. First it was a multi-week hamstring issue, then fractured ribs. Herndon finished the year having appeared in just one game, catching a single pass for seven yards. Not exactly the fantasy eruption we'd hoped to see.

Let's just remember that Herndon is still the same player who made one of 2018's most ridiculous catches...

...and the buzz surrounding him is gonna return this season. New York's receiving corps isn't exactly the league's most talented group, so it's clear Herndon has a huge opportunity ahead. Ryan Griffin remains in the mix, though he's still recovering from ankle surgery. Herndon has a shot at finding the end-zone 6-8 times in the season ahead, which would easily land him inside the position's top eight.

Eric Ebron, Pittsburgh Steelers

54 percent rostered, ADP 130.7

Somehow, Ebron is still just 27 years old. It feels as if we used to draft him alongside Ben Coates and Frank Wycheck, but apparently that is not the case. My research team confirms he is, in fact, 27. Ebron is also just one year removed from a 14-touchdown season in Indianapolis, a year in which he caught 66 passes for 750 yards. We know he's capable of delivering an exceptional fantasy season because he's already done it. No one should be terribly surprised if he emerges as a red-zone weapon for Pittsburgh. Apparently he spent part of his quarantine offseason staying at Camp Roethlisberger, for what it's worth. Ebron is one of the better final-round fliers at his position, considering his team context and recent history.

Ian Thomas, Carolina Panthers

34 percent rostered, ADP N/A

Pretty much everything is new in Carolina in 2020, including quarterback Teddy Bridgewater (previously in New Orleans), head coach Matt Rhule (previously at Baylor) and OC Joe Brady (previously at LSU). It's really a lot of newness in a year without an in-person offseason program. Thomas, however, is a holdover, and he's no longer the understudy to Greg Olsen (now in Seattle). He's a sneaky candidate to see 90-plus targets as the unchallenged No. 1 tight end on Carolina's roster. Bridgewater's short-to-intermediate passing tendencies should help his cause.

Will Dissly, Seattle Seahawks

8 percent rostered, ADP 126.3

For a few games last season, Dissly had the look of a star. He caught 22 of 24 targets for 250 yards and four touchdowns in Weeks 2-5, consistently producing ridiculous highlight plays. An Achilles injury ended his breakout season in October, but his recovery has reportedly gone as well as possible. Dissly cleared his camp physical, which is obviously a good sign. Seattle signed 35-year-old Greg Olsen in the offseason, but this team will roll with plenty of two-TE sets. If Dissly is fully healthy (or anywhere close), we can expect perhaps a half-dozen house calls.

Jace Sternberger, Green Bay Packers

21 percent rostered, ADP N/A

Sternberger played only 60 snaps during the regular season as a rookie, failing to catch a pass. But he saw three targets in the postseason for the Packers and caught 'em all, including a red-zone touchdown reception in the NFC title game...

Green Bay curiously passed on the top receivers in the 2020 draft, you might recall, and veteran Devin Funchess has opted out of the season. So this team desperately needs a serious contribution from Sternberger. He was placed on the reserve/COVID list last week, which of course is no small concern. But if he's back in the mix relatively soon, he has a chance to claim a substantial workload. You can leave him alone in 10 and 12-team leagues, but he's a reasonable flier in deeper fantasy formats.

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