TORONTO (Ticker) -- Mark Prior was not at his best, but managed to cool off the Toronto Blue Jays .

The hard-throwing righthander allowed two unearned runs and seven hits in 5 2/3 innings as the Chicago Cubs snapped the Blue Jays ' five-game winning streak with a 4-2 victory.

Prior (8-2) recorded his third straight win, yielding only a two-run homer to Carlos Delgado in the third inning, one out after Frank Catalanatto reached on first baseman Eric Karros ' error.

"Mark wasn't as sharp as he'd like to be but he battled hard," Cubs manager Dusty Baker said.

Prior, who started the game with five straight strikeouts, walked two and struck out eight in his shortest outing of the season. The three-game winning streak matches a career high.

"Obviously, they are a very good hitting team," Prior said. "I've been watching them on TV the past couple weeks and what they've been doing is unbelievable. Maybe I gave them a little bit too much credit. I was trying to pick on the corners a lot. I felt as good with my fastball as I have in a long time. Fortunately, we only have to face them once."

Delgado hit his major league-leading 22nd homer and increased his RBI total to 76, which also leads the majors. He was held hitless Friday, ending his streak of driving in runs in consecutive games at eight.

Four Chicago relievers combined for 3 1/3 scoreless innings, allowing just two hits. Joe Borowski recorded the final three outs for his 13th save.

"It was a big win for us, to stop their winning streak and to stop our losing streak," Baker added. "Our bullpen did a great job. Our bullpen was a little spent, especially after that rain-delayed game (in Baltimore on Thursday). All the guys, (Kyle) Farnsworth), (Mike) Remlinger, (Antonio) Alfonseca and Borowski, did a great job."

In the seventh inning, Remlinger struck out Delgado, who represented the tying run, looking on a 3-2 pitch.

"To me, that's what relieving is all about," Remlinger said. "If you want to measure how good you are as a reliever, take a look at your inherited runners. I love coming into a game with the tying run on base or whatever the situation may be."

The Blue Jays , however, objected to plate umpire Phil Cuzzi's call.

"We got in a crucial situation there where some words were exchanged," Toronto manager Carlos Tosca said. "I'm sure he (Cuzzi) thought those pitches were strikes and we didn't. It's a situation where we've got our best hitter up there and we'd like to see him have an opportunity to hit."

The Blue Jays threatened with two outs in the ninth as Vernon Wells singled and Delgado walked, but Borowski induced Josh Phelps to ground out to end it.

The Cubs staked Prior to a 3-0 lead in the top of the first as Moises Alou delivered a two-run triple and scored on second baseman Orlando Hudson 's throwing error.

"When I got to second, (center fielder) Wells had the ball, so I knew I was in trouble," Alou said. "I was hoping the ball would hit me because I knew the throw was coming. It hit me in the elbow and I was able to score. Any time you give Prior a three-run lead in the first inning you know you like your chances to win."

Toronto starter Doug Davis (3-4) gave up an RBI single to Ramon Martinez in the second before settling down. He surrendered six hits in six innings.

"Doug got off to a rough start but he battled back and was able to give our team a chance to win," Tosca said.

"I just tried to get ahead early and not walk people, and that's what I did today," Davis added.

The loss also snapped a seven-game home winning streak for the Blue Jays .