TORONTO - Detroit Pistons guard Brandon Jennings will miss the rest of the season after he ruptured his left Achilles tendon.

Jennings was injured in the third quarter of Saturday night's 101-86 loss at Milwaukee. He averaged 15.4 points and 6.6 assists in 41 games this season.

"It's definitely a tough loss for us," Pistons forward Greg Monroe said before Sunday night's game at Toronto. "He's a huge part of the success we've had recently."

Coming into the day, Detroit had won 12 of 16 to climb back into the Eastern Conference playoff race after a terrible start. But it will be difficult to maintain that pace without the 25-year-old Jennings.

Detroit has not reached the post-season since 2009. It's the longest active drought in the East.

The Pistons said there is no timetable for Jennings' return, but the guard tweeted a message earlier Sunday saying "6/9 months."

"Not being able to play basketball is the worst thing," Jennings tweeted in a separate message.

Coach Stan Van Gundy said he feels bad for Jennings, who loves playing "probably as much as anybody I've been around."

"He plays all summer, he loves being in the gym," Van Gundy said. "On top of that, he was having the best season of his career, particularly lately, so it's really tough. It's tough for us but it's even tougher for him and I feel real bad for him because he was playing so well and then to have it end when he was on such a run is really unfortunate."

D.J. Augustin will take Jennings' spot in the starting lineup, with rookie Spencer Dinwiddie coming off the bench.

"We've got confidence in D.J.," Van Gundy said. "He's played very well this year."

Van Gundy spoke to general manager Jeff Bower on the telephone Sunday morning and said he'll look to add a third point guard to the roster "fairly soon."

"We'll meet tomorrow and look at our options and see what it is we think we should pursue," Van Gundy said.

The Pistons have had an open roster spot since waiving Josh Smith last month, but still could apply to the league for a hardship exception, Van Gundy said.

Just as difficult for Detroit will be replacing the swagger and confidence provided by Jennings, whom Van Gundy described as having the "natural personality" of a locker room leader.

"Guys are sort of in that shock time right now," Van Gundy said. "He really thought we were going to kick everybody's butt every night and showed that on the floor. I think that gave his teammates more belief. We're going to need guys to play with that kind of confidence."

Dinwiddie has only played nine games with Detroit this season, and recently spent seven games with Grand Rapids of the NBA Development League.

"This is the opportunity he's been looking for all year," Van Gundy said. "Let's see what he's got."

Dinwiddie, whose final season of college basketball at Colorado was cut short by a knee injury last January, said he was conflicted by way his opportunity arrived.

"It's definitely a laundry list of emotions," he said. "BJ obviously was a really good vet and one of my friends. Obviously anybody is happy to play, you just don't want it ever to happen like that."