Fantasy football owners are preparing their big boards, doing mock drafts and analyzing players’ stats. All of this preparation is in hopes of having a solid draft, which is a key factor for fantasy football success.

One of the most exciting parts about playing fantasy football is finding diamonds in the rough, players that fly under the radar yet produce on a weekly basis for your team. These players are called sleepers, and every year fantasy football owners focus on finding them in their drafts or even on the waiver wire.

Here are the top fantasy sleepers to watch for at every position, including quarterback, wide receiver, running back, tight end, kicker and a defense/special teams. This article is based on standard leagues.

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Quarterback: Jameis Winston, Tampa Bay Buccaneers

OK, the first pick of the 2015 NFL Draft is by no means under the radar, but he might not be high on many fantasy owners’ draft boards. Winston had a decent rookie season. He didn’t amaze the league with 30-plus touchdowns or throw for over 5,000 yards, but he had a solid season for a rookie quarterback. Winston threw for 4,042 yards and 22 touchdowns, along with 15 interceptions for a touchdown/interception ratio of 1.46. Though he only has a year of NFL experience, expect him to continue to improve this season. He has a high football IQ, and coaches have raved about his intellect. He has weapons on offense in wide receiver Mike Evans, wide receiver Vincent Jackson and running back Doug Martin. Winston isn’t a first-round fantasy draft pick, but if you’re looking for a quarterback during the middle rounds, he could be a solid pick-up. 

Wide Receiver: Kevin White, Chicago Bears

White was sidelined for his entire rookie season because of a leg injury. The No. 7 pick in the 2015 NFL Draft, he was considered a top prospect. Coming out of West Virginia, he showed big play potential. He totaled 1,447 receiving yards for the Mountaineers in 2014 and caught 10 touchdowns. White was a Biletnikoff Award finalist. He is coming back healthy for his second NFL season, and if he can stay that way, he can be a viable option at the WR2 or flex position.

Running Back: Thomas Rawls, Seattle Seahawks

With Marshawn Lynch enjoying retirement, Thomas Rawls has the potential to be the Seahawks’ featured running back. In his rookie season he showed potential, rushing for 830 yards and four touchdowns. He  led the league in yards per carry, averaging 5.6. Sleepers are inherently supposed to be mid- to late-round picks—it’s one of the things that makes them sleepers. Rawls, however, can have starter potential, because his yards per carry number propelled him into the RB2 range.

RELATED: Fantasy Football 2014: Sleepers And Busts

Tight End: Martellus Bennett, New England Patriots

The tight end position in fantasy football can make or break a team. Having a tight end like Rob Gronkowski or Jordan Reed can send your point totals through the roof. But drafting a tight end as good as Gronkowski takes a lot of luck. Fantasy owners could get solid value by drafting Martellus Bennett, who will play alongside Gronkowski. The Patriots could run a two tight end set at times, and Tom Brady could look for Bennett when Gronkowski is double-teamed. Last season, Bennett totaled 439 receiving yards and caught three touchdowns with the Bears. Bennett won’t be drafted as high as Gronk, but he could be one of the best flex options in fantasy football—especially if you have Gronk on your roster.

RELATED: Slimmed-Down Jameis Winston Looks To Be In Great Shape For Training Camp

Kicker: Sebastian Janikowski, Oakland Raiders

Truthfully, you shouldn’t pick a kicker until the late rounds. They aren’t as valuable as wide receivers or deep-ball throwing quarterbacks. But like tight ends, kickers can be the difference on your team. Janikowski could be the kicker you need to complete your roster. He is ranked No. 15 in Yahoo’s pre-season rankings. Most fantasy owners will go for the top kickers—Justin Tucker, Stephen Gostkowski and Brandon McManus. Janikowski had 26 field goal attempts last season, ranking No. 24 in the category. But with the Raiders’ offense still young, expect Janikowski to kick more field goals this season. You also need a kicker who can convert extra points; Janikowski succeeded on 97.4 percent of extra points last season. In Janikowski, you get a kicker who can do both.

Defense/Special Teams, Oakland Raiders

The Oakland Raiders’ defense could be one of the best in the NFL this season. With players like defensive end/linebacker Khalil Mack, linebacker Bruce Irvin and rookie safety Karl Joseph, Oakland will field an up-and-coming defense. Last season, they allowed 24.9 points per game, ranking 22nd in the league. This was a subpar performance, but the addition of Joseph, rookie defensive end Shilique Calhoun and defensive end Mario Edwards could make Oakland’s defense a solid option for fantasy owners.