As the season goes on, what you're looking for in a sleeper tends to shift.

Early in the year, uncertainty is still at its peak, and there are guys you can gamble on to break out and become weekly starters for the rest of the year. As the season plays out, roles become more clearly defined, and there are fewer opportunities for that.

At quarterback and tight end, you're generally just looking for players to make a one-week start, either serving as your latest streaming option, or being stop-gap solutions while your usual starter has a bye week.

Running backs and receivers still let us find some season-long value though. Injuries (and this week, trades) open up opportunity for players who haven't seen it yet. These guys are usually unproven, which gives you the chance to get out ahead of your leaguemates and get that player on your roster before their value becomes obvious.

That can set you up nicely for the next few weeks, but those players also tend to be the best available options to plug in as starters, with the waiver wire generally picked clean of obvious starters by Wednesday every week.

Here are 8 fantasy football sleepers for Week 8.