SEATTLE — For James Paxton, Monday was a definite step in the right direction. For Edwin Diaz, it was an encouraging big-league debut. But for the Mariners, it was more of the same.
Cleveland capitalized on a costly error by catcher Chris Iannetta by scoring two unearned runs in the fourth inning, which proved decisive in a 3-1 victory at Safeco Field.
"I was upset about it," Iannetta said. "I wasn’t surprised. I was just upset that I missed it. I’m not afraid of contact. I’ve absorbed a lot of them. I just missed it."
This makes four straight losses for the Mariners, who are 1-5 since the calendar turned to June. That one victory was their remarkable comeback from a 10-run deficit last Thursday at San Diego.
Paxton fell to 0-2 since replacing injured Felix Hernandez in the rotation, but this was a far better effort than the battering he took five days earlier in San Diego.
"I executed a lot better," he said. "Kept the ball down. Worked both sides and really mixed speeds."
Paxton flashed dominant form at times in limiting Cleveland to one earned run in six innings while registering 10 strikeouts.
"That’s the real James Paxton," manager Scott Servais said. "He needs to step up, and he certainly answered the bell tonight."
It just wasn’t good enough because of (a) Iannetta’s error and (b) the Mariners were overmatched by Indians right-hander Trevor Bauer, who improved to 4-2 after giving up just one run and five hits in 7 2/3 innings.
"I thought tonight he really pitched," Indians manager Terry Francona said. "He drove his fastball to both sides of the plate, he really spun some breaking balls, his off-speed was really good."
Bryan Shaw got the final out in the eighth inning before Cody Allen closed out the victory with a scoreless ninth. The Indians have won six in a row and lead the American League Central Division by 2 1/2 games.
The Mariners fell four games behind first-place Texas in the AL West.
Diaz made his debut when he replaced Paxton to start the seventh inning. With the crowd of 15,824 cheering him on, Diaz recorded a one-two-three inning by sandwiching two grounders to third around a strikeout.
"After the first pitch," Diaz said, "I told myself, `I’m in the big leagues, and I need to pitch.’ Everything was good."
Generally viewed as the organization’s most-advanced pitching prospect, Diaz, 22, arrived Saturday in a direct promotion from Double-A Jackson less than one month after shifting to bullpen duty to accelerate his development.
The Mariners opened the scoring in the third inning after Ketel Marte singled in his first at-bat after returning from the disabled list.
Marte then stole second with a head-first slide, which is how he suffered a sprained left thumb on May 21 in Cincinnati.
After moving to third on Shawn O’Malley’s grounder to first, Marte scored when Nori Aoki lined a two-out single into center for a 1-0 lead.
That was all the Mariners got against Bauer.
Cleveland answered Aoki’s RBI single with a two-run fourth inning — aided by Iannetta’s inability to hold a throw at the plate.
Carlos Santana lined a one-out single to left, and Jose Ramirez followed with a double into the left-field corner. Santana tried to score from first and should have been out; Marte made an on-target relay from Seth Smith.
The ball got through Iannetta. Santana scored, and Ramirez moved to third, which proved pivotal when Juan Uribe sent a sacrifice fly to right for a 2-1 lead. Both runs were unearned.
Iannetta had a chance to atone later in the inning with two outs and runners at second and third. But he struck out.
Cleveland then extended its lead to 3-1 on Rajai Davis’ one-out homer in the fifth inning. Paxton turned and watched as the ball carried 360 feet to left and arched his back in disbelief when the ball cleared the wall.
That summed up the night.
PLAY OF THE GAME: Catcher Chris Iannetta was his own harshest critic at his inability to hold the relay throw from shortstop Ketel Marte in the fourth inning.
The ball got past Iannetta and allowed the tying run to score and the go-ahead run to reach third base with one out. A sacrifice fly then put the Indians on top.
"I just missed it," Iannetta said. "I just made an error. It never bounced. I just missed it. You’re going to make errors. I don’t want to do it. I pride myself on my defense. I’m really good back there on plays like that.
"I’ve missed three this year that have gone off my glove. One was inconsequential. He would have been safe anyway. The other one was the (Joey) Votto play (in Cincinnati) and now this one tonight.
"I’ll be out early (Tuesday) working on it. It’s been a strength of mine my whole career, and it will be going forward."
PLUS: James Paxton’s 10 strikeouts matched a career high. He also had 10 on Sept. 24, 2013 against Kansas City…Nori Aoki had two of the Mariners’ five hits and their only RBI…lefty reliever Mike Montgomery pitched two scoreless innings.
MINUS: Shortstop Ketel Marte had a rough first inning in his return from the disabled list. Rajai Davis’ leadoff grounder skipped off his glove for a single, and Marte then boxed a routine grounder by Jason Kipnis for an error.…Shawn O’Malley started at second base but went 0-for-3 with two strikeouts. His average is down to .139…the Mariners scored three runs in the last two games after scoring 54 in their previous six games.
STAT PACK: Robinson Cano’s career-best streak of reaching base at least once ended at 34 games when he went 0-for-4 with three strikeouts…the Mariners’ pitchers recorded a season-high 14 strikeouts.
QUOTABLE: James Paxton pushed the radar readings to 100 mph on a couple of fastballs. "Yeah, I guess so," he said. "It was coming out pretty good. I was getting through my pitches and finishing really well."
SHORT HOPS: The Mariners are catching a break in the series in that they will now miss right-hander Danny Salazar, who is 6-3 with a 2.24 ERA. He is battling fatigue in his right shoulder. Cleveland plans to recall right-hander Cody Anderson from Triple-A Columbus. Anderson will start Tuesday. Right-hander Carlos Carrasco will shift from Tuesday to Wednesday.
Bob Dutton: @TNT_Mariners