While Felix Hernandez has been getting most of the publicity with his outstanding season, the Mariners have another one of the American League's top right-handers in Hisashi Iwakuma, who will start in Sunday's series finale against the Red Sox. The Mariners hope to increase their small lead in the AL Wild Card standings. Rookie right-hander Allen Webster will take the hill for Boston as he tries to end his club's seven-game losing streak.
After missing the first month of the season with a sprained finger tendon, Iwakuma is 12-6 with a 2.57 ERA. The 33-year-old from Japan has been dominant of late, going 7-2 with a 1.63 ERA over his last 10 starts and is coming off eight shutout innings with a season-best 11 strikeouts in Philadelphia.
"He's just got quality stuff and he throws from the same arm slot with all his pitches and has command of all of them," said Mariners manager Lloyd McClendon. "When you've got command of three or four different pitches, it's kind of tough to sit on any one thing."
Iwakuma has been the most efficient starter in baseball this season with just four walks in his last 10 starts and 12 in 147 innings over his 21 outings for the year. His 0.73 BB/9 ratio puts him well on the way to shattering Jamie Moyer's Mariners record for lowest walk ratio of 1.61 in 1998.
Since 1893, there have been just five qualified pitchers to record a BB/9 lower than 0.73 in a season: Cy Young (1904), Christy Mathewson (1913 and '14), Babe Adams ('20), Bret Saberhagen ('94) and Carlos Silva (2005).
"He's unbelievable," said Mariners third baseman Kyle Seager. "He just goes right at hitters, throws strikes with all his pitches, gets swings and misses with all his pitches and he works quick, gets ground balls. He's everything you could ask for. He's awesome to play behind."
Iwakuma says he's getting into a groove now after his delayed start to the season when he missed all of Spring Training and didn't make his first start until May 3.
"It's definitely a different year for me," Iwakuma said through interpreter Antony Suzuki. "But the last couple starts I've been having good, quality starts, so I want to keep my strict routine just the way it is and kind of go from here on for another two months."
Webster, meanwhile, has walked 18 batters in five starts for Boston this season, including 11 in his first two outings. But since giving up four runs on two hits and six walks over 2 2/3 innings on Aug. 2 against the Yankees, he's been much better.
He's gone at least six innings in each of his last three starts, posting a 3.86 ERA and .239/.333/.388 slash line. The Red Sox have won two of those three games.
Webster could be pitching with a slightly wounded crew behind him, though. First baseman Mike Napoli returned to the lineup Saturday after missing two games with back spasms. Third baseman Will Middlebrooks strained his right hamstring Tuesday and has been battling through it all week. Catcher David Ross has started twice since missing over two weeks with plantar fasciitis.
In addition to all that, Hernandez hit Xander Bogaerts in the head with a changeup Friday night, and the Red Sox shortstop sat out Saturday while going through concussion protocol.
"Xander, any time you get hit in the head like he did last night and removed from the game, he's got to go through a protocol which he's going through today just to see if there's any concussion symptoms," said manager John Farrell. "That's what's taking place this morning."
Mariners: Leone lives his Fenway dream
Rookie reliever Dominic Leone grew up in Norwich, Conn., about a 90-minute drive from Fenway Park, and had 10-15 family members in attendance when he picked up the win in his first appearance at the historic stadium in Friday's 5-3 victory over the Red Sox.
Leone pitched a scoreless eighth for Seattle, then got his sixth win of the season when the Mariners rallied for five runs in the ninth.
"It was special," Leone said. "It was awesome to run out, especially when they're playing Sweet Caroline. It was a moment I'll never forget. And to pull out the win at the end was huge.
"I came to tons of game here as a kid," he said. "And every time was awesome. It's why this is Fenway Park. People have those type of memories."
The 22-year-old Leone attended Clemson University and the Mariners selected him in the 16th round of the 2012 First-Year Player Draft.
Red Sox: Ortiz will likely play Sunday
Mariners reliever Charlie Furbush hit David Ortiz above the elbow with a fastball in the sixth inning Saturday and the DH exited the game with a left elbow contusion after running the bases following that at-bat.
Farrell expects Ortiz to be ready Sunday and said the slugger got hit "in a pretty good place."
"A little swollen," Ortiz said while flexing his arm on his way out of the clubhouse after a 7-3 loss to Seattle. "But I'll be alright."
Friday night, Ortiz became the first major leaguer to reach base at least four times in four consecutive games played since Joe Mauer did it in 2006. He was the first member of the Red Sox to do it since Mike Andrews in 1970.
But Ortiz reached just twice Saturday and failed to become to first player in franchise history to accomplish that feat five games in a row.
• Since 1910, only two pairs of qualified pitchers on the same team have finished a season each with a WHIP below 1.00 --- Sandy Koufax and Don Drysdale for the Dodgers in 1964 and Pedro Martinez and Derek Lowe for Boston in 2002. Hernandez and Iwakuma, both with sub-1.00 WHIPs, could join that group this season.
• Although reported by several outlets Friday, the Red Sox officially signed Cuban outfielder Rusney Castillo to a seven-year, $72.5 million contract Saturday. He will join a Red Sox Minor League affiliate in the coming days.
• Joe Kelly felt a minor tweak in his shoulder Friday and was removed for precautionary reasons. But after undergoing more tests Saturday morning, the team's medical staff determined he's on track to start Wednesday in Toronto.
The righty exited Friday night's game against the Mariners after just five innings and 88 pitches. He had allowed one hit and three walks in his best start with the Red Sox to date --- he came to the club with Allen Craig from St. Louis on July 31 in exchange for John Lackey.
Steven Petrella is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.