SEATTLE -- Buck Showalter has been around the game of baseball long enough to understand that a three-game losing streak in early July is no reason to panic. More at the top of the Baltimore manager's list of concerns is a pitching staff that's running out of gas as the Orioles crawl toward the All-Star Break.

"The teams that do the best are the ones that have healthy arms at the end," he said after another short outing from his starting pitcher in a 12-6 loss to the Seattle Mariners on Saturday night.

The Mariners belted five home runs to hand Showalter and Orioles their third consecutive defeat. Mike Zunino, playing in his first game of the season, homered twice, while teammates Nelson Cruz, Seth Smith and Adam Lind also went deep for Seattle (42-39). Home runs by Zunino, Cruz and Smith opened up an 8-1 Seattle lead over the first four innings.

"We need to win some games to get back into this, and I just wanted to help any way I could," Zunino said after the win.

Baltimore (47-33) lost its third game in a row despite 12 hits, one short of the Orioles' cumulative total in the first two games of the series. First baseman Chris Davis hit his 21st home run of the season and drove in three runs.

Starter Tyler Wilson was unable to get an out past the third inning. He allowed eight runs off nine hits over three innings. Wilson (4-6) gave up a career-high three homers and left the game with the Orioles trailing 8-1 in the bottom of the fourth.

"He's not the only one," Showalter said. "We've just not been able to get deep in games with our starters."

Asked late Saturday night whether the taxed pitching staff will need some additions to make it to the All-Star Break, Showalter said: "We've got some plans in place. We're working on it right now."

The Orioles have lost three in a row for the first time since Toronto beat Baltimore from June 10 through 12.

Seattle had 16 hits, one shy of its season high, with Lind getting four of them on a single, two doubles and a solo homer. Smith went 3-for-5 with four RBIs.

"Everyone's hitting well right now, so it's nice to be a part of it," Smith said after homering in a third straight game for the first time in his career.

Mariners starter James Paxton (2-3) earned the win despite a shaky outing that saw him give up four runs -- three earned -- on nine hits over 5 2/3 innings.

"I was hoping to get him a little deeper," manager Scott Servais said. "He lost focus there in the sixth inning."

Every member of the Mariners' lineup scored or drove in a run, led by Smith's four RBIs. Zunino drove in three runs with his two homers.

Baltimore mounted a rally by scoring six runs off 10 hits in the fourth, fifth, sixth and seventh innings, but the early deficit proved too large to overcome.

The Orioles had the bases loaded and two outs in the sixth, but Adam Jones popped out to end the threat.

Seattle came back in the bottom of the sixth and scored three more runs, two of them coming on back-to-back homers from Lind and Zunino.

The Mariners used home runs from Nelson Cruz and Zunino -- in his first at-bat of the season -- to jump out to a 5-0 lead before Wilson got his first out in the second.

Smith added a three-run homer, marking the first time in his career that he has hit home runs in three consecutive games, to give Seattle an 8-1 lead in the fourth inning.

Cruz crushed the first pitch he saw from Wilson for a 459-foot homer that hit the facade of the upper deck in left field, resulting in a three-run homer. Cruz's 21st home run of the season gave Seattle a 3-0 lead with one out in the first.

After Lind led off the second with a double to left, Zunino hit a 1-2 pitch to the same part of the field but cleared the wall for his first major league home run since Aug. 15, 2015.

"A really big night for our offense," Servais said. "Guys swung the ball great, top to bottom."

The Orioles got one run back on a Chris Davis RBI single in the fourth, cutting the Mariners' lead to 8-1.

Smith's ninth home run of the season, and his third of the series, opened an 8-0 lead in the fourth while chasing Wilson from the game. He allowed eight runs and nine hits in three innings, giving up a season-high three homers in the process.

"You've got to tip your hat to (the Mariners)," Showalter said. "But also, we're making a lot of mistakes."

NOTES: Baltimore's Chris Davis tied Ken Singleton for eighth in the Orioles' list of career home runs with his 182nd Saturday night. ... Seattle C Mike Zunino made his season debut. Zunino, the No. 3 overall pick in the 2011 draft, spent the second half of 2015 and the first three months of this season in Triple-A before an injury to backup C Steve Clevenger opened the door for a return to the Mariners. ... Seattle's bullpen was limited Saturday night, as two of the most productive relievers on the team were being given the night off. Rookie Edwin Diaz and closer Steve Cishek both worked in back-to-back games and weren't likely to be available. ... The four-game series wraps up Sunday. Seattle will begin a seven-game road trip with a Monday game in Houston. The Orioles will spent the holiday in Los Angeles, where they will begin a three-game interleague series against the Dodgers. ... Saturday marked the halfway point of the Mariners' season. The Orioles will play Game No. 81 on Sunday.