ESPN analyst Ben Solak identifies one X-factor player for each NFL team ahead of the 2026 season, defining them as individuals who can dramatically swing their team's fortunes. Solak excludes quarterbacks, coaches, and rookies to highlight less obvious difference-makers. For the Arizona Cardinals, wide receiver Marvin Harrison Jr. is the pick.

Under new head coach Mike La Fleur, Harrison could see more diverse usage after lining up out wide on 78.6% of targets over the past two seasons. The Cardinals lack proven above-average starters beyond safety Budda Baker, edge rusher Josh Sweat, tight end Trey McBride, and wideout Michael Wilson, making Harrison's breakout critical. Last year's X-factors included Kenneth Walker III, George Pickens, and Stefon Diggs on the positive side, while Keon Coleman, Broderick Jones, and Sir Vocea Dennis disappointed.

Solak notes the exercise reveals as much about roster holes as individual talent, with selections spanning all 32 franchises from the NFC West to the AFC East.