Fantasy Football Week 15 Start Sit: Mariota’s Favorable Matchup Outshines Nix’s Tough Test

Washington Commanders quarterback Marcus Mariota is the clear fantasy football start over Denver’s Bo Nix for Week 15. This critical decision hinges on starkly different defensive matchups this Sunday. Mariota faces the struggling New York Giants, while Nix meets the stifling Green Bay Packers.

The choice impacts fantasy playoffs and championship hopes for managers. According to trusted fantasy analysis and NFL performance data, the Giants’ weak secondary presents a prime opportunity. The Packers’ elite pass defense, however, poses a severe risk for Nix’s production.

Bo Nix Faces a Daunting Packers Defense

Denver’s Bo Nix has produced middling fantasy results recently. Since Week 11, he ranks as just the QB20 in standard fantasy formats. His Week 14 outing against the Raiders saw him throw for 212 yards with no passing touchdowns, though he added a rushing score.

The matchup against Green Bay is exceptionally difficult. The Packers allow the seventh-fewest passing yards per game this season. Over their last three games, they have been even better, yielding an average of only 154 passing yards. This environment suggests a low-ceiling game for Nix.

Marcus Mariota Gets a Giants Defense in Disarray

Marcus Mariota steps in for the injured Jayden Daniels with a superb fantasy setup. In his last start in Week 13, Mariota threw for 294 yards and two touchdowns. He also added 55 rushing yards, providing a valuable dual-threat floor.

He now draws a New York Giants unit that has been a gift to opposing quarterbacks. They allow the ninth-most passing yards per game in 2025. In their last three games, they surrendered two 270-yard passing performances and allowed every quarterback they faced to throw two touchdowns.

The Week 15 fantasy football start sit decision leans heavily toward Marcus Mariota. His combination of recent performance, rushing upside, and dream matchup makes him the superior play. Bo Nix, facing one of the league’s hottest pass defenses, is a clear sit in most fantasy leagues this week.

A quick knowledge drop for you

Why is Marcus Mariota a good start this week?

He faces the New York Giants, who have one of the weakest pass defenses in the NFL. Mariota also offers rushing upside, which provides a safe fantasy floor even if his passing numbers are average.

What is the main concern with starting Bo Nix?

He plays the Green Bay Packers, a top-five pass defense over the last month. Their ability to limit quarterback production makes Nix a high-risk, low-reward fantasy option for Week 15.

How has Mariota performed as a starter this year?

In his Week 13 start, he was productive, passing for 294 yards and two scores while rushing for 55 yards. That performance demonstrates his capability as a fantasy streamer in a positive matchup.

Can Bo Nix’s rushing help his fantasy value?

It can, but not enough against Green Bay. He had a rushing touchdown last week, but the Packers’ defense is likely to limit overall scoring opportunities, capping his ceiling significantly.

Is this a season-long recommendation or just for Week 15?

This is strictly a Week 15 analysis based on the specific matchups. Both quarterbacks’ fantasy value will change weekly based on their opponents and team situations.