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Jason Vargas had an uncharacteristically poor outing in his first start after being named AL pitcher of the month for May, and the Los Angeles Angels were forced to use a rookie reliever in the 10th inning in a tough spot against Anthony Rizzo of the Chicago Cubs.

Robert Coello surrendered a three-run double to Rizzo, and Los Angeles went on to an 8-6 loss on Wednesday night. Mark Trumbo homered twice, but the Angels still had to settle for a split of the two-game series against the Cubs.

Kevin Gregg (2-0) managed to hang on for the victory against his former teammates after striking out Mike Trout with the potential winning run at third base in the ninth and fanning Hank Conger for the final out with two on in the 10th.

Howie Kendrick homered and had four hits for the Angels, who have lost seven of 10 following an eight-game winning streak. He was 7 for 8 in the two games, and is 12 for 22 for his career against Cubs pitching.

"We put up a pretty good effort today, and that's what you want to see," Trumbo said. "Unfortunately, they were just a little better."

Rookie Robert Coello (3-2) walked Dioner Navarro with one out in the Cubs' 10th and Darwin Barney singled with two outs. Barney advanced on catcher's indifference and Luis Valbuena walked before Rizzo doubled lined a 2-1 pitch into the right-field corner, increasing his team-high total to 39 RBIs.

"I faced him a few times before in the minor leagues, so I know that's what he likes to do — throw the fastball in that spot," Rizzo said. "He has a splitty, too, but I know he doesn't like to throw that with runners on. So I looked for the fastball and tried to lay off everything else."

Vargas, who went 5-0 with a 2.30 ERA in six starts last month, gave up five runs and 11 hits in five-plus innings. The left-hander took a 4-1 lead into the fifth before Navarro and Barney singled and Cody Ransom hit his fifth homer of the season.

"The difference was the homer to Cody Ransom. That's what got them going," Vargas said. "I feel like I made a dumb mistake. We're up three runs and I decide to go after him like it was a pretty close ballgame. Three runs isn't a huge lead, but it was definitely a mental mistake on my part. Just go ahead and go after him and make him beat us the hard way. I left a changeup up to him and that really let them back in the ballgame. I feel like that cost us the game."

A nice running catch by Trout on Welington Castillo's drive to the warning track with runners at second and third later that inning prevented the Cubs from taking their first lead of the game. But the Cubs managed to go in front in the sixth when Starlin Castro led off with a double, Navarro reached on an infield hit and Ryan Sweeney chased Vargas with an RBI single.

"It was one of those rare games the last three weeks where the pitching didn't get it done," manager Mike Scioscia said. "Offensively we did enough to win a game, but we're still not firing on all cylinders."

Now that the Angels' 3-5 homestand has ended, Scioscia is going back to a regular five-man rotation. Jerome Williams is the odd man out because he is better suited to a relief role than either Tommy Hanson or Joe Blanton, who lost a 2-0 decision Monday night against Houston despite allowing three hits in eight innings and tying a career high with 11 strikeouts.

Williams is 3-1 with a 2.14 ERA over his last five starts, including seven innings of three-hit ball in a 2-0 loss to Houston on Saturday.

"Sometimes it's tough for an individual when there's five spots and six guys pitching well," Scioscia said. "It's just where we are right now and what the needs of the team are. I think Jerome has an opportunity to be a 'wild card.' His preference is to start, and he's certainly put his best foot forward and done a terrific job with that. But he definitely understands the situation and wants to help the team in any role."

Matt Garza pitched 6 1-3 innings for Chicago in his fourth start off the disabled list and allowed four runs and seven hits, including Kendrick's eighth homer, which matched his entire total from last season — in 324 fewer at-bats.

Garza benefited from a video replay reversal in the second after J.B. Shuck's towering drive past the right-field pole was originally called a home run by first base umpire Jeff Nelson.

Shuck came up against Garza again with one out in the seventh and hit a fly ball to the warning track that was dropped by Nate Schierholtz, who had just taken over in right field for Scott Hairston after hitting for him.

Shuck ended up at third on the error, but was stranded there when Sweeney sprinted toward right-center and robbed Albert Pujols of a potential two-run double with runners at the corners. Sweeney was making only his third start in center while David DeJesus got the day off.

NOTES: Prior to Chris Iannetta's RBI single on a 2-2 count in the fourth, opposing batters were 2 for 34 against Garza with two strikes on them. ... The Angels begin a six-game road trip Friday night at Boston, trying to extend an eight-game winning streak against the Red Sox.