After the game, Buccaneers coach Bruce Arians expressed concern about Evans' status moving forward, saying the wideout's hamstring injury was "not good."
"I'll be shocked if he makes it back before next week," Arians said following a 38-35 victory over the Colts, per ESPN's Jenna Laine.
Evans has been one of the NFL's most productive wideouts since entering the league in 2014, and entering Sunday, he had registered 66 catches, 1,096 yards and seven touchdowns on the season.
The two-time Pro Bowler has topped 1,000 receiving yards in each of his five NFL campaigns entering 2019, and despite the Bucs switching between Jameis Winston and Ryan Fitzpatrick at quarterback on a couple of occasions last season, Evans set a career high with 1,524 receiving yards.
While Evans has been a cornerstone of Tampa's offense for his entire six-year career, he became an even more important piece during the offseason.
With the Bucs moving on from DeSean Jackson and losing Adam Humphries to the Tennessee Titans in free agency, their receiver depth took a considerable hit, as it left Evans and Chris Godwin as the only established wideouts on the roster.
Additionally, Winston entered 2019 on the final year of his rookie contract, and he needed another big year from Evans to prove he was deserving of an extension.
Tampa has relied heavily on its passing game in recent years, and with Arians now at the helm, the philosophy hasn't changed much.
The Bucs don't have much in terms of proven running backs, so they can ill afford to be without Evans for long since it will have a hugely negative impact on the passing attack.
If Evans does land on the shelf for any period of time, Godwin will be the clear No. 1 wideout with former first-round pick Breshad Perriman and second-year man Justin Watson also figuring into the mix.
Winston is likely to target skilled tight end O.J. Howard and backup Cameron Brate even more in the passing game until Evans returns.