"I don't have an answer," Vinatieri said Thursday. "I don't know. We'll see how it feels tomorrow and the next day and the next day."
Vinatieri, the NFL's all-time leading scorer, showed up on the Colts' injury report Wednesday -- for the first time this season -- as a limited participant in practice because of the knee. He's awaiting the results of an MRI.
"Felt [pain] a little bit last week and through the game [against Tennessee on Sunday]" and then again Wednesday, Vinatieri said. "Just a little more sharp than what it was before."
Vinatieri said he is meeting with general manager Chris Ballard and the team's medical staff Thursday afternoon, and that should help provide clarity on whether he plays again this season or goes on injured reserve.
Despite working out 11 kickers at two different times this season, the Colts have stuck with Vinatieri even though he has made a career-low 68% of his field goal attempts. He has missed 14 kicks: eight field goals and six extra points. Two of Vinatieri's misses -- against the Chargers and Pittsburgh -- cost the Colts games. Three of his kicks have been blocked, including one that was returned 63 yards for a touchdown against Tennessee this past Sunday.
The Colts added insurance when they claimed kicker Chase McLaughlin off waivers Wednesday in case Vinatieri isn't able to play against Tampa Bay on Sunday. Vinatieri, 46, hasn't missed a game due to injury since the 2009 season, when he also had a knee injury.
"If I can go, I'll go," said Vinatieri, who didn't kick during practice Thursday.
McLaughlin has played in seven games this season, four with the Los Angeles Chargers and three with the San Francisco 49ers. He was 13-for-17 on field goals and made all 15 of his extra point attempts.
Vinatieri's current knee injury is similar to what he dealt with in training camp, when he was shut down for a period of time. It has bothered him sporadically throughout the worst season of his 24-year career.
"If you can be on the field, you do everything you can to be on the field," Vinatieri said.
If this season is Vinatieri's last, he'll finish his career with the record 2,671 points and 29 game-winning kicks. Three of Vinatieri's most memorable kicks came with the New England Patriots from 1996 to 2005. He hit a winner in blizzard-like conditions against Oakland in the 2001 playoffs and winning kicks in Super Bowls XXXVI and XXXVIII.