ANAHEIM -- After winning nine games in their most recent 11-game homestand, the Blue Jays looked like they were gaining momentum to make a run at the top spot in the American League East. But a 6-3 loss to the Angels in Game 1 of Tuesday’s split doubleheader at Angel Stadium was a bit of a gut check.

Steven Matz, who is aiming to keep his spot in Toronto’s rotation when it drops down from six starters to five, tried to keep the team’s momentum going. However, the left-hander allowed four runs (two earned) in 4 2/3 innings, throwing 59 of his 97 pitches for strikes.

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"I think it's a good problem to have, when you have six legit guys who can go out and start the game," Matz said of the rotation plan. "For me, it's not a motivator. I work as hard as I can to be the best that I can every time I'm out there. It's kind of out of your hands."

Matz pitched around traffic in the first and second innings, but he ran into trouble in the third, when he was one out away from again walking off the mound unscathed. Matz’s sinker didn’t have the cut It needed to be effective in the strike zone, and Phil Gosselin took note of it.

Gosselin connected on a 2-1 sinker a couple inches off the plate and lined it to right field for a two-out single. After José Iglesias doubled, Justin Upton knocked them both in with a single to give the Halos a 2-0 lead.

The Angels extended their lead to 4-1 in the fifth with two unearned runs scoring on a fielding error by Vladimir Guerrero Jr., who lost a popup in foul territory at first base.

Though Matz took the loss, he didn’t see it as a step backward. The movement on his sinker and changeup provided positive results, with a total of 21 called strikes and whiffs between the two pitches, so Matz feels he is moving in the right direction.

"I'm not walking away today like it was a bad outing. Those guys battled, and they hit some singles through the infield," Matz said. "Balls fell. That's kind of how I'm walking away from today, more than anything. Ultimately, it was a loss, and that's very frustrating."

The Blue Jays' offense, which had produced nine runs in Sunday's win over the Red Sox, came up short in this one. Toronto scored a pair of runs in the fifth on Teoscar Hernández's RBI single and Corey Dickerson's RBI triple, but it couldn't come all the way back.

Although the Blue Jays outhit the Angels, 9-8, they went 1-for-8 with runners in scoring position and left seven runners on base.