Thigpen started with an ugly interception but engineered three scoring drives to help the Bills erase a 21-point deficit. Easley returned a kickoff 100 yards for a touchdown and then caught a two-point conversion pass in the fourth quarter.
Whether it will be enough for either to make the 53-man roster will begin to be known at 9 p.m. today, the deadline for NFL teams to trim down from 75 men.
The Bills lost the game, 38-32. The result left Buffalo winless (0-4) for the first time in preseason since 2002 and the 11th time in their 53-year history.
The Bills' starters played Detroit's starters to a 7-7 draw, with the first units playing only one series apiece. But the mistakes came fast and furious when the Bills' backups took the field. Detroit held a 28-7 lead after the first quarter.
The Bills have 10 days to get ready for the start of the regular season, when they visit the New York Jets on Sept. 9.
The Bills came out of the game without any injuries to their starters, and the first-teamers exited the preseason in good health. Only right tackle Erik Pears, nursing a sore groin, is uncertain to start in the opener.
However, Bills Wildcat quarterback Brad Smith left in the first half with a groin injury. Gailey said he didn't think it was "terribly bad."
Bills quarterback Ryan Fitzpatrick directed an 83-yard touchdown drive on the opening series, capping it with a 4-yard touchdown pass to Stevie Johnson. The march took 11 plays. Detroit was playing without five defensive starters.
"We wanted to start fast tonight and put some points on the board," Fitzpatrick said. "We have a lot of confidence. . I think on offense we feel we are light years ahead of where we were in the past. We are looking forward to getting off to a fast start to the season."
Detroit quarterback Matt Stafford responded by marching the Lions 80 yards in seven plays, capped by a 24-yard touchdown pass to All-Pro receiver Calvin Johnson.
A crowd of about 40,000 at Ford Field watched both teams run "vanilla" offenses, sticking to their basic plays.
Detroit's second-stringers got three quick scores. A fumble by Smith on a kickoff return gave the Lions the ball at the Buffalo 9 and led to an easy touchdown. Then a 30-yard punt return set up the Lions on a short field for another touchdown that made it 21-7.
Then Thigpen threw an interception that was returned 23 yards for a touchdown by Detroit's Jonte Green. It was a quick throw for receiver Derek Hagan, lined up wide left. Thigpen's hand apparently was hit as he released the ball.
The Bills acquired Tarvaris Jackson this week to be the No. 2 quarterback. Thigpen, battling to stick as a No. 3, finished 18 of 30 for 186 yards with one touchdown and two interceptions. Given Jackson's unfamiliarity with the offense, the Bills could decide they want Thigpen on the roster as insurance for the season opener. They also could cut Thigpen then try to re-sign him to a lesser contract before the opener.
"Tyler had his hand hit twice for interceptions," coach Chan Gailey said. "We can't have that kind of penetration in there on those situations."
"Tyler played good," Gailey said. "He made it tough. And it was all on the line. He did a good job. There's some receivers that played well, and they are going to make it a really tough decision as well."
Thigpen drove the Bills 63 yards to a field goal in the second quarter, then 64 yards and 47 yards to touchdowns in the third quarter. The first TD after halftime came on a 1-yard run by Johnny White. The second came on a 4-yard TD pass to tight end Dorin Dickerson. That pulled Buffalo within 28-24.
After a Lions field goal, Easley took advantage of a good block by Kyle Moore to burst up the right sideline and score on a return. Gailey opted to try for a 2-point conversion to avoid the prospect of overtime. After a false-start penalty, Thigpen threw to Easley at the 1, and the third-year receiver bulled just over the plane of the goal line to put Buffalo ahead, 32-31.
But Easley wasn't the only receiver to produce. Ruvell Martin had five catches and Kamar Aiken three. Naaman Roosevelt had two catches and a nice, 20-yard punt return.
"The return team did an excellent job blocking," Easley said. "They made it real easy for me to read. The hole was there and I hit it as hard as I could. I tried to leave it all on the field, just like the rest of the receivers. We all made plays."
After Easley's return TD, Detroit answered with an 80-yard TD drive in just 3:33 for a score to re-take the lead.
"The negative is their offense went right down the field right after that because our defense was dead tired," Gailey said.
For what it's worth, the final tally for the Bills' first-string offense in four preseason games was three touchdowns and one field goal produced in 16 possessions. The starting defense allowed five touchdowns and one field goal in 15 possessions.