The Rangers have now won three in a row and improved to 6-26 when scoring three runs or less. They held an opponent to exactly one run for the ninth time this season, improving to 14-0 overall when allowing one run or less.
The Rangers are 27-21 over their last 48 games and 10-6 in series openers at home.
"Tommy Hunter was real good tonight," manager Ron Washington said. "He kept them off balance. He threw four pitches for strikes. If you can do that, hitters can't sit at the plate and wait for a pitch."
Hunter's last two outings have dropped his season ERA from 5.06 to 3.17. He received three spot starts last season and took three more this season with injured starter Matt Harrison on the disabled list.
That has earned him the nickname of "Spot."
"That's my role," he said, "and I'm going to continue to do it."
Hunter continued a strong stretch of pitching for the Rangers' rotation, which has allowed three runs or less in six of its last nine starts.
"His cutter was working well tonight," second baseman Ian Kinsler said. "He was rushed up last season. It's hard to make adjustments at the Major League level."
Hank Blalock once again provided the difference with his two-run, fourth inning home run to put the Rangers ahead, 2-0.
"Just one pitch cost us the game," said Rays starter Scott Kazmir. "I got him out on the same hanging slider on the at-bat before -- he popped it up. I was trying to go low and away slider to him the whole time. I just wasn't getting it there. He made me pay. You don't throw that pitch to Blalock, anything that's hanging, anything that's up. I got away with it the first time and the second time he made me pay."
Blalock also won Wednesday's game with a two-run, walk-off shot. He now has four home runs over his five starts on this homestand.
"There's no way you could sit him down," Washington said. "When Hank is swinging a hot bat, you gotta ride him."
Friday's home run pushed him past Mark Teixeira for sole possession of fifth place on the all-time list of home runs hit at Rangers Ballpark in Arlington.
The Rays scored their only run in the top of the fifth inning. Pat Burrell led off with a single, but Hunter responded by inducing two outs. Dioner Navarro walked and B.J. Upton singled to score Burrell.
The Rangers answered with another run in the bottom of the inning as Marlon Byrd doubled home Kinsler with two outs.
The defense played well behind Hunter. To end the Rays' biggest threat of the night, second baseman Kinsler made a great snare of a line drive.
Center fielder Byrd made a terrific grab of a fly ball off the bat of Evan Longoria for the first out of the sixth inning. The ball drove him nearly to the wall.
That defensive play didn't go unnoticed by Hunter, who described Byrd's catch as "some ridiculous, I-don't-know-how-he-made-that catch."
Jason Jennings came on in relief of Hunter in the sixth and struck out the first two batters he faced. That gave him six consecutive batters struck out, which is one shy off the franchise record, held by Nolan Ryan. Ryan set that record on July 7, 1991.
Frank Francisco secured his 13th save of the season with a 1-2-3 ninth inning. He got his fastball up to 96 mph and seemed to have better control of the pitch. Francisco allowed three runs when he blew a save on Wednesday.