Playing his final game for at least six weeks, Beltre contributed a single, run scored and several superb defensive plays, helping the Mariners notch a 4-2 victory over the Dodgers before 49,355 in the final Interleague game of the season for both teams.
Left-hander Garrett Olson held the Dodgers to two runs over five innings, relievers Miguel Batista, Mark Lowe and David Aardsma allowed only two baserunners over the final four innings, and Jose Lopez had three hits and two RBIs in the Seattle victory.
The Mariners won the series two games to one and climbed three games over .500 (39-36) for the first time since May 5.
But this win was mostly about Beltre.
While the Mariners flew to New York for the second of three stops on this nine-game road trip, the two-time Gold Glove winner returned to his Los Angeles home to prepare for Tuesday's shoulder surgery, which will remove bone spurs in his left shoulder.
The pain he has experienced the past few weeks has been intense, but he has continued to play. The series finale was no different.
"For me, the story today was about Beltre," manager Don Wakamatsu said. "He has been playing in a lot of pain and he didn't need to play today. But he came in this morning and said he wanted to be with his teammates. He wanted to gut it out."
And that he did, playing all nine innings, making all plays that came his way.
The first out in the bottom of the first inning was a wicked line drive that Beltre had to react quickly, and raise his glove painfully high to make the catch.
He had another putout and four assists.
On offense, Beltre hit a run-scoring single to left field, driving in the first run in a three-run rally that gave the Mariners a four-run lead.
"His presence in this lineup will be sorely missed," Wakamatsu said. "He is such a special player, a special person who brings so much to this club. This win is for him."
Beltre called it "an emotional day," but didn't second-guess his decision to have surgery sooner rather than later.
"It's best for the team and for me," he said. "I hope that when I get back in six, seven or eight weeks, they are still in it. And I think they will. They have the desire and are playing good baseball."
Asked what was going through his mind at that moment, he said, "I am thinking about getting healthy and coming back as soon as possible."
The Mariners stunned the Dodgers for the second straight game, holding one of the best offenses in the Major Leagues to three runs over the last 18 innings of the three-game series.
Seattle pitchers retired the first batter in 17 of those innings.
Olson held the Dodgers to one hit and three baserunners over the first four innings before wobbling a bit in the fifth, when he surrendered half of the four-run lead he had. Dodgers center fielder Matt Kemp, who was unable to catch a ball Lopez hit for a two-run double in the third inning, atoned a little with an opposite-field home run to right field.
The home team added another run on two singles, a sacrifice bunt and a sacrifice fly, but that was it.
"For me, the bullpen really won this ballgame," Olson said. "From the sixth inning on, they were great. Coming in here against a team that that has had a lot of comeback victories and are a really tough team ... they did a tremendous job."
Batista retired the first two batters he faced in the sixth and seventh innings, Lowe retired all three batters he faced in the eight eighth inning, and Aardsma had a 1-2-3 ninth inning for his 16th save in 17 save chances this season.
"The turning point for me was Batista," Wakamatsu said. "It was a hot day and for Batista to go two scoreless innings the way he did was key. He got us deeper into the bullpen."
The Dodgers lost for just the 12th time at home this season and were muffled by the Mariners' pitching in the final two games of the series after scoring eight runs on Friday night.
"We haven't been scoring a lot of runs and you certainly want to seize every opportunity you have," Dodgers manager Joe Torre said, "but we really haven't been able to put enough pressure on the opposition the last few days.
"They can bring some pretty good arms, that bullpen can."
Ichiro Suzuki extended his hitting streak to 11 games with an infield single in the third inning -- his 35th hit of the season that didn't reach the outfield -- but his streak of consecutive games with more than one hit ended at seven.