Iwakuma takes the ball Sunday as the Mariners try to salvage a victory in the finale of their three-game series with the Texas Rangers.
Seattle (34-34) is batting .202 and has plated 10 runs during an 0-5 start to an eight-game homestand. It managed two hits in a 1-0 defeat in Friday's opener before showing some signs of life by collecting 11 singles in Saturday's 4-3 loss.
The Mariners, who are in the midst of their longest slide since dropping eight in a row from April 15-22, stranded multiple runners in the three separate innings Saturday.
"We are in a funk and we've got to find a way to come out of it,'' Mariners manager Lloyd McClendon said. ''We had a lot of good things happen tonight but the one bad thing is we didn't the win.''
Iwakuma (4-3, 2.79 ERA) has lost a career-high three straight starts at home behind a 5.31 ERA. He tossed 16 consecutive scoreless innings while going 1-0 in his first two games at Safeco Field.
The right-hander, though, could use some help from the lineup, as he's been backed by an average of 1.73 runs in Seattle. He allowed three runs in 7 1-3 innings of a 3-2 home loss to the New York Yankees on Tuesday.
He's 2-0 with a 2.57 ERA over his last three starts against the Rangers, allowing two runs in eight innings of a 6-2 win at Texas on May 20.
Robinson Cano will try to help provide Iwakuma with some offensive support, as he's batting .352 in 18 games. However, only four of his 25 hits in that stretch have gone for extra bases.
He drove in one run while getting a pair of singles Saturday, improving to 12 for 32 (.375) with 10 RBIs over his past eight games versus Texas.
Still, Seattle has struggled in nearly every facet while dropping six of eight at home to the Rangers dating to last season, batting .229 while compiling a 5.42 ERA - 6.04 from the rotation.
While the Mariners are trying to avoid falling below .500 for the first time since May 31, the Rangers (34-34) are back at the break-even mark thanks to a three-game winning streak.
Adrian Beltre is hitting .409 with three homers and 11 RBIs in 11 games after connecting for a run-scoring double Saturday. The third baseman, who spent 2005-09 with Seattle, owns a .390 average over his past 18 meetings with his former team.
He's also 10 for 25 with three homers off Iwakuma.
A strong display at the plate may be needed with Texas turning to rookie Nick Martinez (1-3, 4.63), who is 0-2 while surrendering 18 runs and five homers with eight walks in 13 innings over his last three starts. That's in stark contrast to his first two starts after being moved into the rotation, when he went 1-0 while yielding two runs in 11 innings.
The right-hander is coming off his worst performance yet, surrendering a season-high eight runs and two homers in two innings of Monday's 17-7 defeat to Cleveland.
"What we have to do is get him reacclimated to where he was when he first got here - attacking the strike zone and using all his pitches," manager Ron Washington told the team's official website.