Old friend J.D. Martinez didn’t give much chase to it, and why would he. The Tigers outfielder had seen that trajectory before. It took George Springer until the 84th plate appearance and 318th pitch of his major league career to notch his first home run, and it left in a hurry to right field in the fifth inning at Comerica Park. If only the Astros’ rebuilding process could be so fast. Thursday’s 6-2 win over the Tigers was the best game the Astros have played in a while, and the turnaround they’ve needed for about a week now. The last time they had even held a lead was Saturday, in a 9-8 loss to the Mariners — in Dallas Keuchel’s previous start. The combination of pitching and hitting made for an all-around, feel-good day. Even the weather was nice. Keuchel didn’t only out-pitch his former college housemate, Tigers starting pitcher and fellow southpaw Drew Smyly, he quieted a bruising Tigers lineup. He’s the team’s No. 5 pitcher, but he’s also been the most reliable pitcher the team has to start the year. He threw 7 2/3 innings, walked none and struck out seven. He hasn’t walked more than two batters in any of his six outings and the most runs he’s allowed is four — and that was just once. With a very high number of strikes, 79 in 106 pitches, Keuchel has become one of the best in baseball at inducing ground balls. The Tigers scored first Thursday, as they did the entirety of the four-game series, and the Astros fell into a 2-0 hole. Victor Martinez extended his hit streak to 11 games with his third home run of the series, a solo shot, in the fourth inning. Martinez has as many home runs against the Astros this season as he did in all of April.