P.J. Francescon threw seven innings, striking out five batters, but had one key blunder in his start, a three-run home run off the bat of Murray Watts in the second inning. Francescon did not factor in the decision.
In the eighth inning, a throwing error from Wes Darvill set Kane County with runners at first and third base, with no outs. Chiefs relief pitcher Yao-Lin Wang was charged with a balk, allowing Daniel Mateo to score.
With two outs in the inning, Watts delivered another key blow to Peoria, a two-run double, giving the Cougars a 6-3 lead. He finished the game with five RBIs.
"Sometimes, that's the way it goes," said Chiefs manager Casey Kopitzke. "You battle and battle and battle. Sometimes, they get good wood on a ball. You tip you hat to (Watts), he got a pitch and didn't miss it."
The Chiefs brought the potential tying run to the plate, but Cougars third baseman Michael Antonio snagged a hard ground ball, turning it into a 5-3 game-ending double play.
Peoria finished the game 2-for-14 with runners in scoring position, leaving eight runners on base.
"We did a great job getting guys in position, it just comes down to execution," said Kopitzke. "You get guys in scoring positon, it's just a matter of busting out. One big hit changes the complexion of the game."
Chiefs first baseman Paul Hoilman continued his strong play of late, chipping in with two hits and two RBIs. Hoilman's first-inning RBI double extended his hitting streak to 15 games. His batting average has crept up to .294 on the season after a sluggish start.
He's giving us some quality at-bats and is doing a nice job hitting in the middle of the lineup for us," said Kopitzke.
Peoria and Kane County return to action on Thursday night, with first pitch coming at 6 p.m. Jose Rosario toes the rubber for the Chiefs.
"He comes out there everyday and gives us a good outing, a good start," Kopitzke said of Rosario. "He competes. Hopefully we come out on the good end tomorrow."