Hamilton delivered a two-out, pinch-hit double to left-center that scored Prince Fielder from first base with the winning run, moving the Rangers over .500 for the first time in 360 days.
Texas 4, Boston 3.
When the Rangers acquired Hamilton in late April for cash considerations -- the equivalent of a couple of peanut butter sandwiches in baseball lingo -- we figured he'd be average at best.
After all, that's what he was in two miserable seasons with the Los Angeles Angels, who essentially paid him to go away after he had a sobriety relapse in late February.
Well, he has been a blessing for the Rangers. He has played only seven games with the Rangers but has made an impact, offensively or defensively, in virtually every game.
General manager Jon Daniels has already received $2 million worth of performance in Hamilton's first week.
"You know what Josh can do," Adrian Beltre said. "He's been good since he got back home and saw the fans behind him. He's gotten more confidence and that's all he needed."
In seven games with Texas, Hamilton is hitting .272 with six RBIs and five runs scored.
He helped the Rangers beat Boston on Friday with a pair of homers. On Saturday, Hamilton helped Texas secure a win with a two-out walk that started a two-run rally in the bottom of the eighth inning -- doing it after falling behind in the count 0-2.
Sunday was supposed to be Hamilton's day off, but he entered the game with two out and runners on first and third, thanks to an error and an intentional walk to Fielder.
On a 1-1 pitch, Hamilton anticipated a split-fingered fastball from closer Koji Uehara. It's a pitch that tails down and away from left-handed hitters.
That's exactly what Uehara threw, and Hamilton lined it to left-center, where it rolled to the wall.
"I just kind of flicked it out there," Hamilton said. "I've gotten a little smarter. Before, I might have tried to pull it."
The Rangers, an embarrassment at the end of April when they were 7-14 and tied with Cleveland for the fewest wins in the American League, went 19-11 in May.
Much of the credit goes to an offense that spent April in a slumber. Choo, Fielder and Beltre played key roles in the offensive resurgence.
Now, the Rangers must find a way to keep hitting and winning without Beltre for at least the next two weeks.
Beltre sprained his left thumb sliding into second base in the fifth inning while trying to break up a double play. He was fitted for a splint and also needed four stitches.
Beltre, who hit .283 with four homers and 14 RBIs in May, is hitting .257 with six homers and 18 RBIs this season. He had two homers and two RBIs in the Rangers' wretched April.
The Rangers will probably move Hamilton from fifth to fourth in the batting order, which doesn't seem like a big deal. That said, some players prefer to hit cleanup; others don't.
It's all about mentality.
"You can't make up for Beltre," Hamilton said. "You can't replace him."
For what it's worth, Hamilton is a career .266 hitter in the cleanup spot in 765 at-bats. In the fifth spot, where he has been hitting with the Rangers, he's a .345 hitter in 487 at-bats.
And he has a .288 average in 2,108 at-bats as a No. 3 hitter.
Mitch Moreland, the only other real option to bat fourth, has one career at-bat in that spot.
"This has been one of the most fun weeks I've had in baseball," Hamilton said. "Not knowing what situation I was in coming into the clubhouse, but the guys have welcomed me in, and I'm just having fun."
Winning is always fun. And it's obvious a happy, productive Hamilton makes the Rangers a better club.