It's crunch time for fantasy football owners, and many leagues are in the championship weekend or semifinal games this week. If your struggling to find a player for the flex spot, or are in need of a plug and play running back or wide receiver, here are two viable options for this week.

Buffalo Bills RB Karlos Williams - The Bills will be without running back LeSean McCoy this Sunday with an MCL injury, and Williams will look to be the lead back for the Bills' offense against the Dallas Cowboys. McCoy reportedly has a torn MCL, and the team has practiced this week with the anticipation that he will not play, according to ESPN's Mike Rodak. Williams is officially listed as probable with a shoulder injury and is clearly a starter for fantasy owners if he suits up against Dallas. The rookie running back has rushed over 400 yards and scored five touchdowns this year, and he is a dual threat out of the backfield with 72 receiving yards and two touchdowns. Williams has scored a touchdown in six of the nine games he's played in this season, and he could be due for a big game this weekend. Williams has a favorable matchup against the Cowboys' 18th ranked rush defense, as they are giving up over 110 rushing yards per game. If your struggling to fill your flex spot or are in need of a second running back this weekend, Williams looks to be a strong plug and play option in most fantasy leagues.

New York Giants WR Rueben Randle - The Giants offense will be without their biggest playmaker on the field Sunday, as wide receiver Odell Beckham Jr.'s one game suspension was upheld this week. With Beckham's suspension and wide receiver Dwayne Harris listed as questionable with a shoulder injury, Randle is poised to see a ton of targets Sunday night. The Giants are currently fighting for their playoff lives, and Randle, who has been inconsistent at times this season, is likely eager to prove himself on the field against Minnesota. The Giants wide out has caught 51 passes for 638 yards and has scored six touchdowns. At 6-foot-2, 208 pounds, Randle will look to be quarterback Eli Manning's redzone target and could be a great play in point per reception fantasy leagues. Randle was targeted five times against the Carolina Panthers last week and had four catches for 47 yards with a touchdown. Expect Randle's targets to dramatically increase this weekend, and despite Minnesota's strong pass defense, he looks to be a strong option at the second receiving position or flex spot this Sunday.