After missing 18 games with a wrist injury, Lowry played 42 minutes and had 27 points and 10 assists to help the Raptors overcame a 20-point first-half deficit in a 105-102 victory over the Detroit Pistons.
"I wouldn't have played if I had any fear. If I'm going to come back, I'm going to go out there and play basketball with no limitations," Lowry said. "This is what I love to do, and I wanted to go out there and help our guys win a game."
Toronto moved a half-game ahead of Washington for third place in the East.
"We came back and played well in the fourth quarter, but we didn't start the game the right way," Toronto coach Dwane Casey said. "I liked the way we finished, but we can't play that way and expect to go anywhere."
"He's the team," Raptors shooting guard DeMar DeRozan said. "He runs us, and he showed it tonight. There's no words I can put into context that will explain what it means to get him back."
"They scored 37 points in the fourth quarter, and I don't remember us getting a single stop," Pistons coach Stan Van Gundy said. "Our offense wasn't great, but we went into the quarter with a 12-point lead and scored 22 points. You have to win that game."
Valanciunas put the Raptors back in front, and Smith's short jumper spun out with 50 seconds left. DeRozan followed with a 20-footer to give the Raptors a 104-100 lead with 25.6 seconds left.
Kentavious Caldwell-Pope made it 104-102, and the Pistons fouled Valanciunas with 7.1 seconds to play. He split the free throws to put Toronto up three, and Caldwell-Pope and Harris both missed tying shots.
Detroit was playing without starting point guard Reggie Jackson, who has been shut down since March 24 after struggling all season with a knee injury.
"I'm not going to talk about Reggie Jackson tonight," Van Gundy said when asked about missing Jackson's offense late in games. "I'll talk about the players who played, but he wasn't even on the floor."
Raptors: As has become usual with Raptors games in Detroit, Toronto fans made up a large percentage of the crowd. ... Toronto won for the 21st time this season when it trailed at some point by double digits.
Pistons: The game was the next-to-last regular-season contest at the Palace of Auburn Hills -- Detroit's home since 1988. Barring an improbable run into the postseason, the arena's final game will be Monday against the Washington Wizards. The Pistons and Detroit Red Wings both move to Little Caesars Arena this fall, after what is likely to be the first season in which they both miss the playoffs since 1982-83.
New ball, please
The officials had to change the game ball early in the second quarter after an errant Toronto pass sent it sailing into a courtside fan's beverage. The Pistons led 37-17 at the time of the switch, and the Raptors narrowed the margin to 10 at the half.
KCP'S busy day
Caldwell-Pope wasn't expected at the arena after his wife went into labor earlier Wednesday, so Van Gundy was surprised to see him in the second quarter. Caldwell-Pope took his regular rotation spot in the second half but scored only two points. "I didn't even know McKenzie had the baby until I looked over and saw KCP sitting on the bench," Van Gundy said. "I guess we couldn't expect much from him after that kind of day."
Raptors: Host the Miami Heat on Friday night.
Pistons: Visit the Houston Rockets on Friday night.
Once Brooklyn Nets rookie Jarrett Allen gets up to speed with his game conditioning, head coach Kenny Atkinson may give his young center more minutes.
Which players offer the most DFS upside and best values on Friday's slate of NBA action? We have them all for you right here.
It seemed improbable that anyone could rival Isaiah Thomas' fourth-quarter production of last season, but Boston's masked man has turned into a superhero in the clutch.