Jennings scored 35 points, hit a career-high eight 3-pointers and added eight assists for the streaking Bucks, who rallied late in regulation and never trailed in the second overtime in a 114-108 victory over the Kings.
Jennings was reveling afterward in his biggest points total since he scored 55 in a Nov. 14 game at Golden State.
Evans was being examined by team doctors and the rest of his season could be in jeopardy. He sustained a concussion, had lacerated gums and a chipped tooth after taking an inadvertent elbow from the Bucks' Ersan Ilyasova late in regulation on a loose-ball situation when he departed for good with 27.3 seconds left.
Kings officials said Evans was being X-rayed and might have a fractured jaw.
The talented point guard had 15 points, four rebounds and four assists. He had his first triple-double last week and was an assist shy of having two more in the following three games.
"Tyreke has a concussion. He has some damage to his teeth and his jaw," Kings coach Paul Westphal said. "There will be more tests [tomorrow]. He obviously isn't going with us to L.A. [for Sunday's game with the Clippers].
"We have no idea how long he'll be out or how serious the injury is until the doctors are able to examine him with all the equipment they have."
The injury took away from a showcase game between two of the leading candidates for Rookie of the Year. Jennings, who has been annoyed lately over his absence from the Rookie of the Year discussion, downplayed the strong game versus Evans, who many see as the front-runner for the rookie honor.
"Right now it's not about me, it's about my teammates," Jennings said. "John Salmons played today, Andrew Bogut played good today. Ersan hit some big shots. A win like this is like a playoff game. We just kept fighting."
Salmons continues to play well for the Bucks. Since arriving in a trade from Chicago the Bucks are 13-2 with the veteran swingman in the lineup. Salmons scored 27 points, but perhaps more importantly was a major factor in keeping Evans from making his trademark penetrating moves to the basket.
"I was trying to stay in front of him [Evans] as best I could," Salmons said. "He is one of the best at getting in the paint and finishing. My teammates gave me a lot of help."
Andrew Bogut added 21 points and 11 rebounds for the Bucks, who avoided their first two-game losing streak since mid-January. The Bucks hold down fifth place in the Eastern Conference playoff chase and are 2 1/2 games ahead of sixth-place Charlotte, which lost to Atlanta in overtime.
The Bucks scored the first five points of the second overtime and never trailed.
Jennings hit a jumper with 1:12 left for a 112-108 lead and the Kings never scored again in a sloppy final minute.
"We were able to steal it," Bucks coach Scott Skiles said. "We were able to execute well after some timeouts and got some baskets and Ersan Ilyasova hit the big one. We were fortunate to have that on a night where we didn't play well."
In the first overtime, Jennings missed a jumper in the closing seconds that would have won the game. Neither team scored in the final 59 seconds and went into the second overtime tied at 101.
Ilyasova sent the game into overtime, making a long 3-pointer to tie it at 95 with 6.4 seconds left. The Kings squandered a nine-point lead in the final 2:26.
The battle of the two talented rookies definitely belonged to Jennings in the first half. He made five 3-pointers and had 22 points for Milwaukee, which led 49-48.
Bucks forward Carlos Delfino was back in the starting lineup after missing the last two games because of left ankle bone bruise. ... The Kings ended their five-game homestand and will play six of their next seven on the road, starting Sunday against the Clippers.