SEATTLE -- Right-handed pitcher Jeff Weaver took one step closer to returning to the rotation, throwing a simulated game before Sunday's series finale against the Rangers.

Weaver, sidelined with right shoulder tendinitis, struggled before being placed on the disabled list, compiling an 0-6 record with a 14.32 ERA.

Sunday's session, though, offered Weaver and the Mariners some encouragement.

"I felt stronger as I went on," Weaver said. "My sinker was working well, and my breaking balls were sharp."

Bench coach John McLaren, acting as manager until Monday while Mike Hargrove is in Ohio attending his daughter's high school graduation, said a return date is still uncertain, but that will be one of the topics of conversation upon Hargrove's return.

McLaren also said Weaver looked good in the simulated game.

"He threw nice and free and easy," McLaren said. "He had real good command, and he was finishing his pitches."

Weaver has been disappointing for the Mariners so far this season after signing a one-year contract worth more than $8 million. He's given up 50 hits and 35 earned runs in just 22 innings.

With a simulated game under his belt, the 30-year-old is one step closer to returning, something he's been anxiously awaiting.

"I've been antsy for about 10 days now," Weaver said. "I'm ready to get back out there, no doubt about it."

Beltre still out: Mariners third baseman Adrian Beltre was still absent from Sunday's lineup, two days after leaving Friday's game with a sprained left thumb.

McLaren said Beltre wanted to hit in Weaver's simulated game, but the Mariners weren't about to take any chances with Beltre hurting himself any worse.

"We had to wrestle [Beltre] out of the batting cage because he wanted to hit off Weaver," McLaren said. "The guy is the ultimate gamer."

Beltre is day-to-day with the injury, and Willie Bloomquist, who recorded two hits in place of Beltre on Saturday, was in the lineup again on Sunday.

Love for Lou: Former Mariners skipper Lou Piniella was suspended indefinitely by Major League Baseball for a tantrum he threw in the Cubs' 5-3 loss to Atlanta on Saturday, but has some of the Mariners' sympathy.

The tirade, which included his trademark move of kicking dirt on the umpire's shoes, was no surprise to McLaren, who spent 15 seasons with Piniella in Tampa Bay, Seattle and Cincinnati.

McLaren said he tried to contact Lou, and left a message for his long-time friend.

"There's nobody that wants to win more than Lou," McLaren said. "I relayed on to him that we're thinking about him. We know he's frustrated, and better things are to come."

McLaren said Piniella must have modeled his kicking motion after Cleveland Browns' All-Pro kicker Lou Groza.

"Knowing Lou like I do, he needed to get that out from inside of him," McLaren said. "He'd been holding that in for a long time, and I do think he got most of it out, and he had his Lou Groza kick, which I thought was appropriate."

Skip's return: McLaren talked to Hargrove after Saturday's win over the Rangers, and said the conversation was much more enjoyable than the one after Friday's loss.

Hargrove listened to the game on the Internet while home for daughter Shelly's graduation.

McLaren, who also acted as manager under Piniella, said he enjoyed his time at the helm.

"It's been fun," he said. "I'm looking forward to Grover being back [Monday]."

Lowe back in town: Righty Mark Lowe returned to Seattle on Saturday, the first time he's been back since having right elbow surgery in April.

Lowe threw on flat ground just outside of the Mariners dugout prior to Sunday's game.

"Lowe is continuing his throwing program," McLaren said. "I know he's really happy to be here and be with the guys."

On deck: The Mariners play the first of a three-game series against the Orioles on Monday at 7:05 p.m. PT. Ace Felix Hernandez (3-3, 4.10 ERA) faces off against southpaw Erik Bedard (4-3, 3.67).