Haren gave up five runs to a Twins team that had totaled only 11 while losing six of its last seven, had his shortest start in more than six years and lost to a Rule 5 Draft choice who stifled the Angels' inconsistent offense in a 5-0 defeat.
Haren, one of baseball's most consistent starters over the last eight years, needed 78 pitches to get through a 3 2/3-inning outing that saw him give up eight hits -- four for extra bases -- and walk two to end a stretch of 13 consecutive quality starts by the rotation.
The 31-year-old right-hander -- now 1-3 with a 4.19 ERA -- chalked it up to a lower back that stayed tight throughout the night and didn't really allow him to get much on his pitches.
"A lot of times you start loosening up throughout the game, and today it was kind of the opposite," said Haren, who doesn't expect the back ailment to affect him moving forward. "It just progressively got a little bit worse.
"I think it was pretty obvious. I didn't strike anybody out, I walked a couple guys, gave up a lot of hits to a team that had been really struggling. So I think my results speak to how I felt."
Tuesday was Haren's shortest start since Sept. 7, 2005, and was just the third time in his 10-year career that he didn't record a strikeout during a start. With that, the Angels snapped a three-game winning streak and were unable to notch their first four-game winning streak of the season.
"It's unfortunate," Haren said. "We had some momentum and I kind of just laid an egg."
Once again, so did the offense.
They were held scoreless by 25-year-old soft-tossing lefty Scott Diamond, whose seven-inning gem -- four hits, one walk, six strikeouts -- paved the way for the Angels' seventh shutout of the year, which leads the Majors. In the process, Albert Pujols went 0-for-4 with four groundouts and is batting .190.
The Angels (13-18) seemed to be building some momentum heading in, winning six of their last eight and notching three straight double-digit-hit games for only the second time this season.
But consistency is something this offense continues to search for.
"Baseball, it's the funniest game in the world," said second baseman Howie Kendrick, one of four starters to record a hit. "One day you'll be on top of the world and the next day you'll be at the bottom. Something'll happen one day -- I can't even tell you when that is -- and everything will just click. I don't think anybody expects to win every game, but I think we've been doing a pretty good job of playing some good baseball lately. Today just happened to be one of those days we got shut out."
Diamond is just one of many starters who have held the Angels scoreless this year.
There was also Henderson Alvarez and Brandon Morrow of the Blue Jays, who hurled shutouts on consecutive days last week. There was David Price, who recorded only his second career shutout on April 24. There was the 38 consecutive strikes Bartolo Colon threw in his eight scoreless innings on April 18. And there was the Indians' Derek Lowe and the Yankees' Hiroki Kuroda, each of whom held the Angels scoreless in their outings.
"We wanted to work in and attack hitters," said Diamond, a recent callup who was taken in the 2010 Rule 5 Draft and posted a 5.08 ERA in seven big league starts last year. "I think we stuck to that game plan all night long. It seemed to be pretty effective, so we kept working with it. I didn't mix in a ton of changeups, but I was able to keep them off-balance by working in and out."
After a night in which they went 0-for-5 with runners in scoring position, the Angels rank 12th in the American League in runs and 11th in OPS -- two categories the division-rival Rangers, now 7 1/2 games up, lead in.
"It sucks," Kendrick said. "I'm not going to tell you it's good. But at the same time, you have to take the good with the bad, and hopefully there's a lot of good coming."