Hisashi Iwakuma will return to the Mariners rotation in 2016. / Wiki Commons

Mariners GM Jerry Dipoto Thursday described the return of Hisashi Iwakuma to the Seattle rotation as “a gift to the organization, the city and the fan base from our ownership.”

Dipoto, who negotiated with Iwakuma from September to the first part of December only to have the righthander sign with the Los Angeles Dodgers, added, “This was an opportunity to do the right thing. We reunited a player who wanted to be here with a team that wanted him.”

Iwakuma, who has been with the Mariners since 2012, couldn’t come to terms with the Mariners on the length of a contract and agreed to join the Dodgers Dec. 6 for a reported $45 million over three years. But the Dodgers didn’t like the results of Iwakuma’s physical exam earlier this week and backed out of the deal, leaving open the possibility that Iwakuma would still sign, but under different terms.

Instead, Dipoto and the Mariners pounced on Iwakuma’s sudden availability.

“It took everybody in the front office less than five minutes to get on board with this,” said Dipoto. “It’s rare to have a group so fundamentally in line. After that, it came together very quickly. We are very excited to bring him back. It’s a good day for us and it puts a finishing touch on what has been a productive offseason.”

At a news conference Friday at Safeco Field, Iwakuma sounded gratified at his return: “I felt love, passion and needed here more than anything else, and that’s why I”m here.”

With Iwakuma’s return, the Mariners have more starting pitchers — Felix Hernandez, Taijuan Walker, James Paxton and newcomers Wade Miley and Nathan Karns — than they have rotation slots, an ideal situation as far as Dipoto is concerned.

“If you line up our rotation and add Hisashi, that gives us the kind of depth we want to get,” Dipoto said. “If you think you’re going to get through the season with five starters, you are fooling yourself. The average team is going to use 10 starters. We wanted to make sure we had enough depth to deal with that. I’m’ very comfortable that now we will put together a good rotation by Opening Day.”

Dipoto would not disclose the terms of Iwakuma’s deal, but conceded that the “structure of the deal” is different than the one Iwakuma rejected.

Iwakuma signed a one-year deal with Seattle worth $10 million in 2016 and received a $1 million signing bonus. The Mariners also have $10 million options in 2017 and 2018. Iwakuma would receive a $1 million buyout if either is declined. The 2017 option would become guaranteed at $14 million if Iwakuma pitches 162 innings next season, and the 2018 option would become guaranteed at $15 million if he pitches 162 innings in 2017 or 324 combined over the next two years.

In addition to other innings-pitched bonuses, Iwakuma will receive eight business-class airplane tickets annually to Japan. He also has a no-trade clause.

“Everybody is comfortable,” said Dipoto. “The situation has righted itself and we’re thrilled. There was no mistaking the fact he wanted to come back. He’s always been comfortable here and his family is comfortable here. This hit the sweet spot for everybody.”

Dipoto also said he never harbored qualms about bringing Iwakuma back despite the negative results of his Dodgers physical.

“We’ve always been comfortable with his medical circumstance. We know his history as well as anybody. This was very simple,” he said.

The 34-year-old Iwakuma went 9-5 with a 3.54 ERA in 20 starts with Seattle last season, including 4-2 with a 2.17 ERA with 43 strikeouts in his final seven starts. Seattle won 11 of his final 16 starts when he went 9-4 with a 2.82 ERA with 97 strikeouts.

The highlight moment of Iwakuma’s season came Aug. 12 against Baltimore when he threw the fifth no-hitter in franchise history (fourth by a single pitcher) and became the second Japanese-born pitcher with an MLB no-hitter (Hideo Nomo twice).

In four seasons with Seattle, Iwakuma is 47-25 with a 3.17 ERA and 551 strikeouts in 111 games, including 97 starts. Since joining the Mariners rotation July 2, 2012, his 3.09 ERA as a starter is the fourth-best in the American League. Iwakuma ranks behind just Felix Hernandez (2.89), David Price (2.89) and Chris Sale (3.05) in the AL.

Notes

With Iwakuma’s return, the Mariners made two corresponding moves Friday. They traded LHP Tyler Olson to the Dodgers in exchange for a player to be named later, or cash considerations. They also designated OF Dan Robertson for assignment to clear a roster spot for Iwakuma.

The Mariners designated the 26-year-old Olson for assignment Dec. 16 to make room on the roster for RHP A.J. Schugel. Olson appeared in 11 games as a reliever for Seattle last season (1-1, 5.40 ERA) and spent the rest of the year at AAA Tacoma following a stint on the disabled list.

The Mariners claimed Robertson, 30, off waivers from the Angels Nov. 6. Robertson split last season between the Angels and AAA Salt Lake City. In parts of two MLB seasons with the Angels (2015) and Rangers (2014), he combined to hit .274 with 33 runs and 28 RBIs in 107 games.