SEATTLE — It is a constant refrain from manager Scott Servais, almost a mnemonic beat, that all success for the Mariners centers on strong starting pitching.
Hisashi Iwakuma carried a shutout into the seventh inning Tuesday night and, yep, the Mariners responded with a 5-2 victory over the Pittsburgh Pirates at Safeco Field.
Note, too, this wasn’t Iwakuma at his best.
"I didn’t really have a good bullpen before the game," he said, "but I was able to make my adjustments. I was able to execute and keep the ball down. I stayed aggressive early in the count and stayed ahead."
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Iwakuma struggled to command his split-finger fastball — normally his premier pitch — and relied instead on his curve, which he seemed to throw at slow-mo speed.
"He made pitches and made adjustments," Servais said. "I think it says a lot about the professional that he is. Figuring out this is working or that isn’t working."
The Mariners built a five-run lead for Iwakuma by scoring single runs in the third and fourth innings against Pittsburgh starter Jonathon Niese before mounting a three-run rally with two outs in the fifth.
Nelson Cruz capped the three-run burst with his 20th homer — a no-doubt, two-run shot to left for a 5-0 lead.
Iwakuma lost his shutout after yielding a leadoff double in the seventh inning to Gregory Polanco, who moved to third on Andrew McCutchen’s fly to center.
Starling Marte then pumped an RBI triple into the right-center gap. Iwakuma retired Matt Joyce on a pop-up, but David Freese lined an RBI single into center. The lead was down to 5-2.
When Adam Frazier followed with a single, the Mariners replaced Iwakuma (7-6) with right-hander Edwin Diaz, who stranded two runners by retiring Jordy Mercer on a fly to short right.
Diaz pitched a one-two-three eighth inning before Steve Cishek closed out the victory for his 18th save in 22 chances. The Mariners edged back over .500 at 39-38.
This was a bounce-back effort for the bullpen, too, after letting a possible victory slip away Sunday by permitting six runs over the final four innings in a 11-6 loss to St. Louis.
Diaz was the key; he faced four batters and retired all four, including two on strikeouts. He has 21 strikeouts in 12 2/3 innings while compiling a 2.13 ERA in 11 outings since making the June 4 jump from Double-A Jackson.
"Ever since he got called up to the big leagues, a young rookie," Servais said, "there’s no fear. He’s very aggressive by nature. He’s in a good spot mentally. He’s not scared. He goes after them."
The Mariners opened the scoring after Leonys Martin started the third inning with a single past third. Shawn O’Malley followed with a bunt single and, when Niese (6-6) threw wildly to first, Martin reached third.
Martin scored on Ketel Marte’s double-play grounder.
The Mariners extended their lead to 2-0 in the fourth inning after Robinson Cano led off with a single and went to second on Dae-Ho Lee’s one-out walk.
Kyle Seager lined a ball off the right-field wall but settled for a single when both runners held up to see whether the ball would be caught. Cano then scored on Chris Iannetta’s sacrifice fly to center.
Only a fine running catch by Andrew McCutchen prevented Iannetta’s drive from being an extra-base hit and resulting in multiple runs.
Cano’s third single of the game, with two outs in the fifth, made it 3-0. Franklin Gutierrez worked a two-out walk and moved to second on a wild pitch before Cano grounded a single up the middle.
Cruz followed with a booming homer to left and it was 5-0.
"Two outs and nobody on, a walk,’ Servais said. "You never know what happens. A ball in the dirt, a base-hit and we score a run. Now a homer. You look up it’s a three-spot. That’s how we need to continue to play."
PLAY(S) OF THE GAME: Shortstop Ketel Marte ranged to his right to backhand Starling Marte’s grounder in the fourth and turn it into an inning-ending double play.
Center fielder Leonys Martin ran down David Freese’s fly ball in the fifth inning and threw to first to double-up Matt Joyce, who had reached on a leadoff single.
PLUS: Robinson Cano went 3-for-4 and raised his average to .303…Kyle Seager also had three hits, while Dae-Ho Lee had two…Shawn O’Malley had a bunt single in four at-bats and is batting .316 (6-for-19) over his last nine games.
MINUS: Maybe it was worth the gamble with two outs, but third-base coach Manny Acta tried to score Dae-Ho Lee from first on Kyle Seager’s double to left-center field. Lee’s speed slowed badly between third and home. Pittsburgh shortstop Jordy Mercer made a strong throw to the plate after taking the relay from Andrew McCutchen. Catcher Chris Stewart blocked the plate and made the tag. The Mariners challenged, but the replays clearly supported umpire Ben May’s call.
STAT PACK: Nelson Cruz’s homer in the fifth inning enabled him to reach 20 for an eighth straight year. He is the only player with a current eight-year streak. The only other players who entered this season with seven-year streaks were Boston designated hitter David Ortiz (who currently has 18) and New York Yankees catcher Brian McCann (10).
QUOTABLE: "It just says that I’m able to play a lot of games," Nelson Cruz said after reaching 20 homers for an eighth straight year. That’s how you put up the numbers. You just don’t throw them out there.
"You’ve got to play games, too, to put up the numbers. That’s all you can ask as a player — stay healthy and play a lot of games."
SHORT HOPS: Pittsburgh manager Clint Hurdle and hitting coach Jeff Branson were ejected by home-plate umpire Ben May for barking on a called strike to Matt Joyce in the fifth inning. Joyce had argued a called third strike in his previous at-bat. Branson was ejected first. Hurdle got the thumb when he came out to argue…the Mariners had multiple players reach three hits this season for the eighth time…Nelson Cruz leads the majors with 71 interleague RBIs since 2012.
Bob Dutton: @TNT_Mariners