Jamaal Williams was already a productive option in fantasy football even when D'Andre Swift was healthy and leading the Detroit Lions' backfield, so naturally, expectations were high for Williams in Week 4 as he was thrust into the spotlight with Swift sidelined by injury.

Those expectations were met, and then some. Williams as a primary option delivered an RB5 finish — his second straight top-five positional finish — with 19 carries for 108 yards (including a long of 51) and two touchdowns as the Lions came up short in Sunday's 12-touchdown, 93-point bonanza against the Seattle Seahawks.

Williams is fantasy's RB3 overall, averaging 17.3 points per game. He leads the NFL in rushing touchdowns, with six to his name. And he's been a playable option all season for a Lions offense that leads the league in scoring (35 points per game) and yardage (436.8 per game).

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But Williams' sustainability — and that of the Lions' fantasy carnival as a whole — is about to be tested in a big way, starting with a Week 5 matchup against a New England Patriots defense that is among fantasy's toughest in RB points allowed (15.5 per game, fourth-best).

Detroit also has dates coming up with the Dallas Cowboys in Week 7 and the Green Bay Packers in Week 9, two top-10 defenses when it comes to points and yards allowed. And don't forget the Lions have a Week 6 bye, which isn't going to help if you're leaning on Williams right now.

Our fantasy analysts rank Williams as the No. 22 FLEX option for the week — the RB11 overall — just behind CeeDee Lamb (WR9) and in front of Tee Higgins (WR10).

Here's the FLEX position — check out where Williams and the rest of the FLEX options landed in our analysts' rankings for Week 5:

2022 Fantasy Football Rankings powered by FantasyProsECR ™ - Expert Consensus Rankings