ARLINGTON -- The Rangers brought right-hander Jonathan Hernandez to the big leagues as a reliever on Tuesday, even though he has been a starter for most of his Minor League career. He passed his first test in Wednesday night's 8-7 Rangers victory by pitching 2 1/3 scoreless innings and getting the win in front of his family in his Major League debut.

The transition to reliever began at Double-A Frisco a few weeks ago after Hernandez went 4-7 with a 5.19 ERA and 1.49 WHIP in 16 starts. Hernandez was having trouble repeating his delivery and holding the same arm slot over 5-6 innings.

The Rangers shifted him to the bullpen, hoping that it would be easier to do so in shorter outings. He pitched only 18 innings over six relief appearances, but the Rangers saw enough improvement to warrant a promotion to the big leagues.

“For the time being it’s the best role,” Rangers manager Chris Woodward said. “His arm slot is better, all the things he was working on are better. We wanted to make sure he could be consistent rather than trying to go five or six innings. He wasn’t consistent at all. He was losing it.”

Left-hander Brett Martin made a similar transition last summer, and he is now a key member of the Rangers’ bullpen. This doesn’t necessarily mean Hernandez will stay in the bullpen.

“We don’t want to give up on him being a starter, but now he is in a good place,” Woodward said. “They did a really good job in our Minor League system of getting him to understand how to be consistent with his slot. He was so inconsistent, he couldn’t control anything.”

Woodward said the Rangers could use Hernandez in a starting role in September and let him pitch 2-3 innings as an extended opener.

“See how many pitches he can maintain it,” Woodward said. “If it starts to go south, we can replace him with somebody else. I don’t want to give up hope on [starting] because I’d really like for him to be a starter in the future. His stuff is so good. He has amazing stuff.”

Hernandez is the No. 12 ranked prospect in the Rangers’ farm system, according to MLB Pipeline. He has a sinking fastball that hits 95-98 miles per hour with a slider that was ranked as the best breaking pitch in the Carolina League last season. Now he’s in the Major Leagues.

“It has been unreal the past few days,” Hernandez said. “It’s hard to believe I am here. This is a dream come true.”

Kiner-Falefa sent down

The Rangers have optioned infielder Isiah Kiner-Falefa to the Minor Leagues and called up left-handed pitcher Locke St. John. Kiner-Falefa is scheduled to play for Frisco on Wednesday night and then will be assigned to Triple-A Nashville.

Kiner-Falefa was called up at the beginning of August to play third base, but he was hitting .225 (9-for-40) with just two doubles and three RBIs. The Rangers want him to get regular time at shortstop and third base, and he is expected to be recalled in September.

The Rangers are not planning to use him extensively at catcher anymore, although he could still be used in an emergency situation.

Burke to stay in rotation

Woodward made it official. With Joe Palumbo on the injured list with a blister on his left thumb, Brock Burke will stay in the rotation and start on Sunday against the White Sox.

Burke earned the assignment with six scoreless innings against the Angels on Tuesday night. He allowed four hits, walked two and struck out four.

A few other points:

• Burke maxed out at 95.3 miles per hour on his fastball.

• He only got five swinging strikes out of 99 pitches, while there were 29 foul balls. So batters were able to at least get a piece of his stuff, hence only the four strikeouts. Woodward said that will get better as Burke learns to elevate his fastball in the strike zone, rather than keeping it down.

• Burke was able to limit the quality of contact. Of 17 batted balls against him, only five were hit with an exit velocity of 95-plus mph. That is a 29.4 percent hard-hit rate, and the American League average is 38 percent.

Rangers beat

• Pitcher Jesse Chavez celebrated his 36th birthday on Wednesday.

• The Rangers went into Wednesday’s game leading the Majors with 98 stolen bases. The only time the Rangers have led the AL in stolen bases was in 1972.

• Right-handed pitcher David Carpenter, who was designated for assignment on Monday, has been assigned outright to Nashville.