Building NFL DFS lineups for Week 15? See what SportsLine DFS guru Jacob Gibbs has to say before you lock in your NFL DFS picks. He can help you put together the optimal NFL DFS picks on sites like DraftKings and FanDuel. He'll also help you decide whether you can trust potential fill-in starters like Seahawks quarterback Drew Lock and Packers running back Patrick Taylor.

Gibbs uses a data-driven approach that has helped him consistently provide accurate rankings at every position. He has proven to be one of the nation's most accurate Fantasy rankers in recent years, posting the eighth-most accurate results over the past few seasons, according to Fantasy Pros.

One player Gibbs is especially high on: Packers rookie receiver Jayden Reed ($4,900 on DraftKings, $6,300 on FanDuel). Gibbs is also rostering Bears receiver D.J. Moore ($6,900 on DraftKings, $7,900 on FanDuel). Moore has benefited significantly from Justin Fields' return, and his splits vs. man coverage present Moore with sky-high upside against an aggressive Browns secondary. No receiver has been better against man coverage than Moore has when he's had Fields at quarterback this season.

Gibbs also is calling for an underpriced running back you aren't even thinking about to score 15 to 25 points on DraftKings and FanDuel! This player could be the difference between winning BIG or going home with nothing.

So who are the best players to target at each position in Sunday NFL DFS lineups? And which underpriced running back puts up a MONSTER point total? ... Join SportsLine here to see Jacob Gibbs' weekly Fantasy Football Helper, all from one of the nation's most accurate experts!