The No. 1 overall draft pick shrugged off two interceptions -- the first he'd thrown in a month -- and benefited from a defensive holding call that wiped out his goal-line fumble in the final minute to score on a 1-yard quarterback keeper the beat Dallas 10-6 Sunday.
Tampa Bay (4-5) won for the third time in five games, doubling their victory total from last season, when the Bucs went 2-14 and earned the opportunity to select Winston, the 2013 Heisman Trophy winner.
"I'm always confident," Winston said after scoring the winner with 54 seconds remaining. "You know, never let them see you sweat. My body language is always good."
The Cowboys (2-7) have lost seven in a row without injured quarterback Tony Romo, the team's longest skid since 1989. Five of those losses have been by a touchdown or less.
"Ultimately, you have to do what's necessary to win the game," Cowboys coach Jason Garrett said. "You have to make the stops and make the plays. We all know that."
The Bucs won for the first time since 2005 when scoring 10 points or fewer, taking their only lead when Winston faked a handoff to Doug Martin and circled right end all alone, one play after the defensive holding call that erased the fumble that might have enabled Dallas to hold on to win 6-3.
"The touchdown was magical," Winston said. "Had a great fake, a great call, found the way into the end zone. The play before that I have no recollection."
The Cowboys (2-7) reached the Tampa Bay 44 following the ensuing kickoff, but Matt Cassel's throw to the end zone intended for Dez Bryant was intercepted by Bradley McDougald after the Tampa Bay safety appeared to give the receiver a slight shove in the back.
Bryant argued for a pass interference call to no avail. The star receiver, who made headlines the past week with a profanity-laced tirade aimed at reporters, later said while he expected a penalty to be called, he nevertheless should have done more to make the catch.
"I felt they were going to call it. They didn't. It's unfortunate," Bryant said. "I'm not going to sit here and make a ton of excuses. I know the standard that I have for myself."
The Bucs (4-5) drove 56 yards in nine plays for the winning score.
Winston completed 22 of 39 passes for 264 yards, including a 17-yard throw to Brandon Myers to help get the Bucs into position to win the game. On third-and-goal from 5, the 6-foot-4, 230-pound quarterback scrambled up the middle and dived for the end zone, losing the ball before crossing the goal line.
But safety Jeff Heath, who had two interceptions to stop Tampa Bay threats, was flagged for holding receiver Mike Evans in the end zone. Winston scored his fourth rushing TD of the season on the next play.
"We're not the same old Bucs. We are trending this direction," coach Lovie Smith said, motioning upward. "I'm just anxious to see what we can do the second half of the season."
Cassel was 19 of 31 for 186 yards and one interception in what may be his final start for the Cowboys before Romo returns from a broken left collarbone that's sidelined him throughout the longest Cowboys slide since they also lost seven straight on the way to a 1-15 finish.
After throwing four interceptions and losing a fumble during a 14-point loss to Carolina on Oct. 4, Winston went four straight games without a turnover. Heath's interception in the second quarter, stopping a drive that reached the Dallas 26, ended the quarterback's streak of 134 consecutive passes without a pick.
Cowboys owner Jerry Jones strongly suggested this week that Romo will start as soon as he is eligible to return next week at Miami. Cassel is 0-4 and Brandon Weeden 0-3 in Romo's absence.
With Vincent Jackson out for the third consecutive game with a knee injury, Evans had eight receptions for 126 yards for Tampa Bay.
Bryant had five catches for 45 yards for Dallas, which was limited to field goals of 42 and 53 yards in the first half. Bailey also missed a 48-yarder in the second quarter, ending a stretch in which he made 21 in a row dating to last season.
The Cowboys played without LB Sean Lee (concussion) and lost CB Morris Clairborne with a hamstring injury in the first half. ... The game-winning drive was the second of Winston's career. ... The Bucs limited Dallas to 42 yards rushing on 21 attempts. Darren McFadden gained 32 on 17 carries.
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