PHOENIX - Kelly Johnson's homer will be remembered as the big blow in the Twins' 9-6 loss to the Diamondbacks on Saturday, but the problems that doomed the Twins began in the middle innings.

That's when Scott Baker threw 102 pitches over five innings, then had to start the sixth because his spot was due up the next inning. That set the stage for two runs to score.

Then lefthander Glen Perkins was able to face just one batter in the eighth -- giving up a single to Miguel Montero -- before grabbing his right side and having to leave the game. After the game, the Twins said Perkins injured his right oblique muscle and will go on the 15-day disabled list. A pitcher will be promoted Sunday from Class AAA Rochester to take Perkins' spot on the roster.

Then Delmon Young made a meal out of a fly ball to the wall by Juan Miranda as two runs scored.

Then Gerardo Parra popped up a bunt that floated over the charging Danny Valencia at third.

Three batters later, Johnson got a meaty pitch from Capps and put it into the seats as Diamondbacks fans went wild and the few thousand Twins fans in attendance went numb.

Capps served it up, no doubt. But he had so much company Saturday.

Ever since Baker reached the majors in 2005, he's had bouts of failing to finish off hitters. When he's getting strikeouts or inducing grounders, Baker can look as efficient as any pitcher in the game.

Saturday was not that day.

Ryan Roberts, a patient hitter, led off the first with a 10-pitch at-bat and a walk, and Justin Upton walked two batters later. Baker got out of the inning, but not unscathed. He threw 21 pitches.

Baker followed that up with 20 more pitches in the second.

Baker had 1-2-3 innings in the third and the fifth. He finished the fifth with his 102 pitches and should have been removed from the game.

But this is the National League.

The pitcher's spot led off the sixth. When the Twins batted in the fifth, Ben Revere moved into the on-deck circle and Alex Burnett heated up in the bullpen. Baker was coming out before Drew Butera ended the inning with a strikeout.

Twins manager Ron Gardenhire wasn't going to bring in a reliever he probably needed to go at least two innings.

So Baker went to the mound for the sixth.

And after doubles by Stephen Drew and Chris Young made the score 4-2. And Baker was out.

The Twins started out well Saturday, grabbing a 4-1 lead. Valencia homered in the second inning, Young scored on a throwing error in the fifth, Jason Kubel crushed a homer to right in the sixth and Valencia had an RBI single later in the inning.

The Twins scored at least four runs in three consecutive games for the first time this season, which suggests the Twins' offense is getting some traction.

Yes and no.

The Twins got their runs on nine hits, including those two homers, but the Diamondbacks also committed four errors, fueling some of the Twins' success.

It was most evident in the big eighth inning, when the Twins scored twice around three errors to push their lead -- briefly -- to 6-3.

With Justin Morneau on first, Drew ran in but missed Michael Cuddyer's grounder for the first error of the inning.

Valencia worked the count to 2-2 against slop-throwing Aaron Heilman, then flared a single to right.

Upton's throw home skipped by the catcher Montero as Morneau scored.

Heilman, backing up the play, grabbed the ball and misfired to second in an effort to get Valencia.

Cuddyer then sprinted for home and beat the throw, with Heilman getting the error.

But that offensive output, aided as it was by Arizona, went for naught as the Diamondbacks rallied, capped by Johnson's grand slam.