HOUSTON -- General manager Jerry Dipoto did juggle the team's pitching staff heading into Thursday's opener of a four-game series, recalling right-handers Casey Lawrence and Nick Rumbelow from Triple-A Tacoma, though neither appeared in the Mariners' 8-6 win over the Astros on Thursday.
Seattle placed recently acquired reliever Sam Tuivailala on the 10-day disabled list with a strained right Achilles tendon after the right-hander was hurt during a rundown play in Wednesday's loss to the Rangers. Chasen Bradford, another right-hander who threw 3 1/3 innings in relief over the previous two days, was optioned to Tacoma to open the other roster spot.
Lawrence joins the Mariners for the fourth time this season. He's posted an 8.16 ERA in 14 1/3 innings over seven relief appearances but has pitched well in a starting role for Tacoma, registering a 2.69 ERA over 12 starts this season.
The 30-year-old could again fill a relief role for Seattle or potentially be used as Felix Hernandez's replacement in the Mariners' rotation.
"We can use him as a length piece if there's an issue early in a game," Servais said. "He can go four/five innings if we had to. Casey is also very durable and bounces back quick, so if he pitches in an inning tonight and he can back out and give you 2-3 tomorrow."
Rumbelow has posted a 7.84 ERA in eight games with Seattle this season in two prior stints, allowing nine earned runs while striking out eight in 10 1/3 innings. The 26-year-old was acquired from the Yankees in November but missed Spring Training and the start of the regular season with a nerve issue in his neck. He had a 2.25 ERA and one save in 10 appearances for Tacoma.
Bradford is 5-0 with a 3.05 ERA in 37 relief appearances for the Mariners this season. He pitched in three games in his most recent stint after being recalled from Tacoma on Friday, allowing three earned runs in 4 1/3 innings. His 44 1/3 innings are second most among Mariners relievers this season, only trailing the 55 of closer Edwin Diaz.
Tuivailala was acquired from the Cardinals on July 27 in a trade for Minor League reliever Seth Elledge and posted a 1.69 ERA in 5 1/3 innings over five outings with Seattle before injuring his Achilles while trying to chase down the Rangers' Rougned Odor in a rundown between third base and home plate in the seventh inning of Wednesday's game.
"There's a lot of upside there and a lot to like," Servais said. "I'm excited about his future. I just hope the issue with his foot isn't serious."

Worth noting
Robinson Cano went 3-for-4 with a home run, double and two RBIs for Class A Short Season Everett and played seven innings at first base on Thursday night in his third Minor League game while preparing for his return from an 80-game suspension.
Cano is expected to play for Everett through the weekend before joining the Mariners on Tuesday in Oakland.
• Servais said Erasmo Ramirez is likely to throw Saturday in his next Minor League rehab outing as he works back from the strained right shoulder that has had him on the 10-day DL since May 1. Ramirez has made four rehab starts and threw four innings with six hits and four runs (three earned) in his last outing for Triple-A Tacoma on Sunday.
• The Mariners moved Dee Gordon from leadoff to ninth in the batting order for the first time in Thursday's series opener, with Mitch Haniger leading off for the first time in his MLB career.
"Mitch has been very consistent," Servais said before the game. "You're going to get good at-bats. Even when he hasn't been driving the ball or getting a ton of hits, he figures out a way to get on base. It's just a different look. I don't know if this is permanent. If we score eight runs tonight, it may be permanent. But it's just a chance to mix it up."
The move paid off. Haniger went 4-for-5 with a leadoff home run and two doubles in the Mariners' win over Houston.