Antonio Brown missed two-straight practices entering Friday, and now Pittsburgh Steelers coach Mike Tomlin has revealed to reporters that the star wide receiver is "undergoing tests" after experiencing further knee pain.

As ESPN's Jeremy Fowler reported, Brown has not been ruled out for Sunday's critical Week 17 contest against the Cincinnati Bengals, but he came into the weekend after already missing Wednesday's practice due to a "coach's decision" designation and then sitting out again on Thursday with a knee injury.

NFL Network's Aditi Kinkhabwala reported earlier this week that at least two of Brown's teammates expect the Pro Bowl wideout to play against the Bengals, but Ian Rapoport said Friday that the receiver will be listed as questionable on the injury report. Tomlin did not indicate one way or another whether Brown will be available and also did not elaborate on the nature of the receiver's tests.

A perennial all-star, Brown has hauled in 104 passes for 1,297 yards and 15 touchdowns opposite JuJu Smith-Schuster this season. He's also yet to miss a game on the 2018 season, starting all 15 games.

Sunday just so happens to be the most important of the season for the Steelers. With a win, and a loss by the Baltimore Ravens to the Cleveland Browns, Pittsburgh would make the playoffs. Either a loss to the Bengals or a win by the Ravens, however, would leave the Steelers out of the postseason.

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