"If they send me out there, they have reason to," Tucker said. "It's because they think I can make the kick."
Rookie safety Matt Elam sealed the victory with an interception Matthew Stafford's third of the night after raising eyebrows during the week by calling 28-year-old Calvin Johnson "pretty old" and saying the plan was to make the star receiver uncomfortable by getting physical with him.
Stafford threw a 14-yard touchdown pass to Joseph Fauria with 2:21 left, putting Detroit up 16-15. But the Lions were unable to make a 2-point conversion and couldn't prevent Baltimore from setting up its sensational kicker for his 33rd successful field goal in a row.
Tucker's kick went just inside the right upright and barely had enough distance eight days after Denver's Matt Prater broke the NFL record with a 64-yard field goal.
"I definitely felt like I got a lot of leg into it, but it jumped up so high I thought I might have gotten under it," said Tucker, who mentioned in a television interview right after the game that his six field goals also benefited his fantasy football team.
Tucker, who hasn't missed a field goal attempt since he was 0 for 2 in Week 2 at Cleveland, has the NFL's longest streak since Matt Stover made 36 in a row for the Ravens from 2005-06, according to STATS.
"What can you say about Justin Tucker?" Harbaugh said. "When we got the ball there, I think at the 45-yard line, I said, 'Hey, are we kicking this?' ... He said, 'I got it.'"
Detroit (7-7) has hurt its playoff chances by losing four of its last five, falling out of sole possession of first place in the NFC North to third place behind the division-leading Chicago Bears and Green Bay.
"This is a setback, no question," Lions coach Jim Schwartz said. "We had control and now we need help. We have to get two wins and let the rest shake out."
Stafford's three interceptions followed a troubling trend for the franchise.
He has 12 interceptions in his last five games. Not coincidently, the Lions have been able to overcome those miscues well enough to win only one game during the slump.