Carlos Santana homered as the Mariners (50-42) moved closer to the club-record 15-game winning streak set in their last playoff season in 2001. They have won 21 of their past 24 games overall to take eight series in a row, their most since winning 14 straight sets during that 116-win season 21 years ago.
Seattle would match the longest winning streak in the majors this year with a victory in the series finale Sunday, its final game before the All-Star break. Reigning World Series champion Atlanta won 14 games in a row last month.
Crawford chopped a one-out single down the line past first base off Brett Martin (0-5), who was the fifth Texas pitcher and went the last two innings. That scored automatic runner Sam Haggerty, who came on as a pinch runner for Santana, who had an inning-ending groundout in the ninth.
A confident Haggerty told Seattle manager Scott Servais before the inning began that he could steal third base off Martin, and Servais went along with it. "If you feel it, take it," Servais said. "Don't play scared."
"Made our jobs a whole lot easier," Crawford said of the stolen base. "Changed the whole infield. Now a lot of more holes are open, and we have an extra opportunity not to waste an out to try to get him over. Just get him in."
"Today, we had a chance to win the game and we didn't," Texas manager Chris Woodward said. "We didn't make baseball plays today. That's plain and simple. We had a chance to win that game. We should have won that game in my opinion."
Crawford and Santana both returned to the Mariners' lineup. Crawford had missed two games because of a bruised right index finger, and Santana was reinstated from the restricted list after being away from the club for a day after a fire at his home in Florida.
Ty France, who had three more hits to raise his batting average to .306, singled in the third before Santana hit his eighth homer of the season to put the Mariners up 2-1. France had a one-out double in the ninth, but his pinch runner got stranded on base.
Nathaniel Lowe, mired in a 4-for-26 slide, led off the Texas second with a double and scored on a single by Jonah Heim. The Rangers tied the game in the seventh after another leadoff double, this one by hot-hitting Leody Taveras before Elier Hernandez singled to get his first career RBI. Taveras has hit .593 (16-of-27) with six doubles in a seven-game hitting streak.
Chris Flexen (6-8, 3.84 ERA), who is 4-0 with a 2.53 ERA in five career starts against Texas, will take the mound for the Mariners in the final game before the All-Star break Sunday.
"Everybody's just doing their job, pitching in and really keeping a very calm demeanor about them," Servais said. "You're not always going to get the big hit or get a big shutdown inning. But we've been able to do it through the streak, and it has been awesome."
The Associated Press contributed to this report.