DETROIT - Alfredo Simon doesn't overpower opposing hitters, as much as he confuses them.

Using an assortment of pitches that included a curveball that didn't even register on the Comerica Park radar gun, Simon allowed two unearned runs in seven innings as the Detroit Tigers beat the Houston Astros 6-2 on Friday night.

"I think today was really good," Simon said. "This is a park for pitching, because when I get behind in the count, I know I can throw a fastball, and even if they hit a fly ball, it's not easy to hit for a home run."

Simon (5-2) has a fastball that he throws in the low 90s, a curveball, a cutter and a splitter, but late last season he added yet another delivery, one that he jokingly calls a "slow splitter". It resembles the soap-bubble curve throw by Cuban pitchers, and usually comes in at around 55 mph.

Simon also dropped down to throw one pitch sidearm, and still might not be out of tricks. When asked if he had reached the end of his arsenal, he simply smiled and said "no".

"No one ever really knows what he's going to do, including the catcher," said rookie James McCann. "He just kind of feels like doing something and goes for it."

Collin McHugh (5-2) lost for just the second time in his last 14 decisions, giving up three runs on nine hits and a walk in seven innings. McHugh's two losses have been in his last three starts after he had gone unbeaten in 16 outings dating back to last August.

A rare lapse by Detroit's infield defence gave the Astros two runs in the top of the third. With two out, Ian Kinsler misplayed a routine grounder, allowing Jason Castro to score, and George Springer followed with a 420-foot RBI double over centerfielder Anthony Gose's head.

The Tigers, though, came back with three in their half of the inning. After Jose Iglesias and Gose singled to start the inning, McHugh retired Kinsler and Miguel Cabrera. Martinez hit McHugh's next pitch 350 feet foul down the left-field line, then hit an 0-1 fastball into the right-field stands for a three-run homer.

"That's a huge swing in the game right there," said Houston manager A.J. Hinch. "They've got two on and no one out, but we get Kinsler and Cabrera, and then Martinez misses one by a couple inches. At that point, you think you are out of the inning, and then he crushes the next one the opposite way."

Martinez was waived in spring training last year by Houston, and signed a minor-league deal two days later with Detroit. In 165 games with the Tigers, he is hitting .302 with 32 homers and 97 RBIs, but he said he's past any bitterness against his former employers.

"It's nice to hit a homer against anyone, but I feel like I squashed that last year," he said. "Everything happens for a reason, and I'm here now, trying to help the Tigers win games."

Detroit made the game safe with three runs in the eighth. Cabrera singled, took third on Luis Valbuena's error and scored on Rajai Davis's two-out infield single. Davis then stole second before McCann's two-run single.

TRAINER'S ROOM:

Astros: RHP Josh Fields, who left Thursday's game after being hit in the right knee by a line drive, is expected to miss a day or two. "It's not comfortable," he said. "It's pretty stiff. I don't know. I guess we'll see what happens."

Tigers: RHP Justin Verlander, who has not pitched this season due to a triceps strain, is scheduled to throw a simulated game on Tuesday. If that goes well, the team will decide if he is ready for a minor-league rehab stint. ... RHP Bruce Rondon threw 22 pitches in a rehab outing for Triple-A Toledo, and experienced no discomfort. Rondon, who missed all of last season after Tommy John surgery, has been battling a bicep injury since spring training.

UP NEXT:

The Tigers and Astros play the third game of the weekend series Saturday afternoon, with Kyle Lobstein (3-4, 4.29) facing Lance McCullers Jr. (0-0, 1.93). McCullers, making his second career start, will face the Tigers 25 years after his father joined Detroit in a trade with the Yankees on June 4, 1990.