He will replace Jameis Winston, who has started the past three games but has thrown eight interceptions in those games, two of which the Bucs lost.
“It don’t like switching quarterbacks,” Koetter said. “It’s not in my nature to change quarterbacks. But I just feel we’ve got to make a switch at this time.”
Koetter noted that the Bucs are last in the league in turnover ratio at minus-13.
“This is really about we just have to do a better job of protecting the football,” he said.
Winston threw four interceptions, one in the end zone and another the Bengals returned for a touchdown, in the Bucs’ 37-34 loss in Cincinnati Sunday.
Koetter said two of the interceptions were the result of bad throws and two were the result of bad decisions.
The 35-year-old Fitzpatrick led the Bucs to a 2-1 record during Winston’s three-game suspension to start the season and is 2-2 in four starts this season. He came off the bench on Sunday to lead Tampa Bay’s rally from an 18-point second-half deficit to tie the game.
However, the Bengals won the game on a late field goal.
Koetter said the move at quarterback is not necessarily a permanent change.
“Just for right now,” Koetter said. “Right now the most important thing we’ve got is this week, so we’ll just see how things go.
“Very rarely is switching quarterbacks forever. Jameis, I’m sure, will get another chance at some point, and when he does, he just has to do a better job of taking care of the football.”
The head coach noted that having a backup as effective of Fitzpatrick is what made this move possible.
“(Many teams) don’t think their backup can do the job,” he said. “Many teams don’t like their first quarterback, let alone their second quarterback.”
After Sunday’s game, Winston blamed himself for the loss.
“I know I’m definitely the reason we came up short in this game and I own that,” he said. “And I have to fix it. There’s not much that I can really say.”
Winston, the No. 1 overall pick in the 2015 NFL Draft, has been the Bucs’ starting quarterback throughout his career. He missed the first three games of this season because of an NFL suspension, and Fitzpatrick started the first game after Winston’s return.
Koetter did not speculate on whether Winston’s three-game suspension contributed to his struggles.
This season Winston has six touchdown passes and league-high 10 interceptions, while Fitzpatrick has thrown 13 touchdown passes with five interceptions.
For his career, Winston has 75 touchdown passes and 54 interceptions.
–WR DeSean Jackson asked for a trade from the Buccaneers that was reportedly denied by the team prior to their game against the Cincinnati Bengals on Sunday, according to the NFL Network.
–DT Vita Vea, the team’s first-round draft pick, was feared to have torn his ACL in Sunday’s 37-34 loss to the Cincinnati Bengals, but an MRI revealed that the ACL was intact.
–RB Peyton Barber had a season-high 85 rushing yards on Sunday.
–WR Mike Evans had six receptions for a season-high 179 receiving yards on Sunday. It was his fourth game this season with more than 100 receiving yards.