PHILADELPHIA — Nelson Cruz’s sore left hamstring is feeling better, but it’s not good enough, manager Scott Servais believes, to risk possible renewed problems by playing in the outfield for the first time this season.

So with no designated hitter available under National League rules, Cruz was restricted to pinch-hitting duties Tuesday when the Seattle Mariners opened a two-game series against Philadelphia at Citizens Bank Park.

“We’ll see how he is (Wednesday),” Servais said. “He is moving a little bit better with the hamstring. Not great. When you’re on defense, it’s different. You can’t control it. You see the ball in the air, you’re going to go after it.

“On the bases, at times, you can control it.”

Losing Cruz strips the Mariners of their hottest hitter. He had a 15-game hitting streak snapped Sunday against Texas but is batting .319 and leads the Mariners with seven homers and 28 RBI.

“He’ll be available (to pinch hit) anytime, any place,” Servais said. “Unfortunately, you can only do it once.”

Cruz started 48 games last season in right field but has only served this season as the designated hitter. The Mariners started an outfield Tuesday of Guillermo Heredia in left, Jarrod Dyson in center and Ben Gamel in right.

Surgery for O’Malley

Utilityman Shawn O’Malley is expected to miss at least a couple of months after undergoing arthroscopic surgery Monday to clean up problems in his right shoulder.

It’s been a rough year for O’Malley, who underwent an emergency appendectomy on March 21. He began the season on the 10-day disabled list and was shifted May 2 to the 60-day disabled list.

O’Malley, 29, batted .229 last season in 89 games with two homers and 17 RBI.

Rehab updates

— Right-hander Felix Hernandez began playing catch Monday in his recovery from bursitis in his shoulder. Lefty James Paxton is expected to begin playing catch later this week in his recovery from a strained left forearm muscle.

General manager Jerry Dipoto previously indicated Hernandez and Paxton could be ready to rejoin the rotation at some point in the upcoming homestand from May 15-21.

— Veteran reliever Steve Cishek threw a 25-pitch simulated inning Monday and is expected to start another rehab assignment later this week in what projects as the final step in his recovery from October surgery to repair a torn labrum in his hip.

— Outfielder Mitch Haniger is showing improvement in his recovery from a strained right oblique muscle, but he is not expected to return on the next homestand.

“You’re probably looking at the next road trip (May 23-30),” Servais said. “He’s going to have to get out and play three or four (rehab) games before he joins us. He’s not picked up a bat yet.”

Pitching plans

Right-hander Hisashi Iwakuma is a firmer choice to start Thursday’s series opener in Toronto. Iwakuma is recovering from a bruised left knee after being hit by a line drive in a May 3 start against the Angels.

The Mariners used an open date Monday in their schedule to push Iwakuma’s start back from Tuesday to Thursday in hopes of avoiding another patchwork fix in their rotation.

Servais said a starting pitcher for Saturday’s game in Toronto is yet to be determined. Lefty Dillon Overton filled that slot in the rotation’s previous cycle but lasted just 3 1/3 innings in last Sunday’s 4-3 victory over Texas.

Fien to Philly

Veteran reliever Casey Fien is coming to Philadelphia but not to rejoin the Mariners’ bullpen.

The Mariners traded Fien, 33, on Tuesday to the Phillies for cash considerations. He was sent to Triple-A Tacoma on an outright assignment May 3 after clearing waivers.

Fien allowed 10 runs in six innings in six big-league outings over two tours. He allowed two runs in 5 1/3 innings at Tacoma in five games.

Root Sports streaming

While Root Sports reached an agreement this week with MLB Advanced Media to begin streaming Mariners games on digital devices to authenticated pay subscribers, the deal does not include Comcast customers.

Comcast chose not to participate.

That means the streaming service will not be available to large portions of Tacoma and Pierce County. For Comcast customers, Root Sports Northwest on cable TV will remain the only viewing option.

The following cable companies are participating: 3 Rivers Communications, Access Montana, Ashland Home Net, Beaver Creek Cooperative Telephone, Clear Creek Communications, DirectLink, DirecTV, Hood Canal Communications, Inland Networks, KPU Telecommunications, LocalTel Communications, Mid Rivers Communications, MINET, Northland Communications, Nemont, PMT, Rainier Connect, Whidbey Telcom, and Zito Media.

Looking ahead

Three things to note heading into Wednesday’s pitching matchup between right-hander Yovani Gallardo and Philadelphia right-hander Zach Eflin.

— Gallardo is 4-0 with a 3.08 ERA in four career starts against the Phillies and won his only previous start at Citizens Bank Park (in 2013) despite giving up five runs in 5 2/3 innings. Eflin has never faced the Mariners.

— Ex-Mariners outfielder Michael Saunders is 1-for-4 with five walks in nine career plate appearances against Gallardo. Outfielder Daniel Nava is 2-for-8 with a walk in nine plate appearances.

— Shortstop Jean Segura is the only Mariner who has faced Eflin. He went 0-for-2 with a walk last year in one game.

Minor details

Hi-A Modesto lefty Anthony Misiewicz was picked Monday as the California League pitcher of the week for May 1-7. He pitched seven shutout innings, while allowing one hit, on May 4 in a 4-1 victory over Lake Elsinore (Padres).

It was Misiewicz’s first victory of the season. He is 1-1 with a 3.56 ERA in six starts for the Nuts. Misiewicz was scheduled to start Tuesday at Lancaster (Rockies).

The Mariners selected Misiewicz, 22, in the 18th round of the 2015 MLB Draft. He was 7-10 with a 4.79 ERA last season in 29 starts for Hi-A Bakersfield.

Short hops

The Mariners entered the series with a 15-8 mark against National League opponents since Servais became manager. …Entering Tuesday, the Mariners had used 20 different pitchers. Only the Angels, with 21, had used more. … Former Mariners pitcher Aaron Harang (2013) turned 39 on Tuesday. He also pitched for the Phillies in 2015. … Former Mariners infielder Matt Tuiasosopo (2008-10) turns 31 on Wednesday.

Looking back

It was 28 years ago Wednesday — May 10, 1989 — that Mark Langston carried a perfect game and a two-run lead into the ninth inning at Toronto.

Langston lost his perfect game when Tom Lawless started the inning with a pinch single. Bob Brenly’s one-out double scored Lawless, and Langston then surrendered a game-tying single to Junior Felix

Mike Schooler replaced Langston and got the inning’s second out before allowing a walk-off single to George Bell in a 3-2 loss. In a span of six batters, Langston went from a perfect game to a loss.

Langston made just two more starts for the Mariners before a May 25 trade sent him and pitcher Mike Campbell to Montreal for pitchers Randy Johnson, Brian Holman and Gene Harris.

On tap

The Mariners and Phillies conclude their two-game series at 10:05 a.m. Pacific time Wednesday at Citizens Bank Park when right-hander Yovani Gallardo (1-3 with a 4.46 ERA) opposes Philadelphia right-hander Zach Eflin (0-0, 2.42).

The game can be seen on Root Sports Northwest and heard on 710 ESPN and the Mariners Radio Network, including mariners.com (for subscribers to MLB.tv).

The Mariners head to Toronto after the game and open a four-game weekend series Thursday at the Rogers Centre.