When the Hokkaido Nippon Ham Fighters seized their franchise’s seventh Pacific League pennant on Wednesday, it was in, appropriately enough, a pitching duel.

After all, the difference this season for Nippon Ham was its pitching and defense.

A year ago, the Fighters finished a distant second, 12 games back of the Fukuoka SoftBank Hawks, but under pitching coach Masato Yoshii, the club’s ERA improved from 3.62 in 2015 to a league-best 3.06. The pitching improved dramatically, the hitting improved slightly, and with SoftBank having lost slugger Lee Dae-ho, the Fighters were ready to step in.

Yoshii, who had been a Fighters coach from 2008 to 2012, spent last season running the Hawks’ bullpen, where he received high marks for his efforts. But he turned down the Hawks’ offer to become their third team manager.

“It was our good luck that Yoshii came back,” top Fighters executive Toshimasa Shimada told Kyodo News. “A lot of our improvement is traceable to him.”

Right-hander Kohei Arihara, a questionable selection as 2015 rookie of the year, has been the bulwark of the rotation, going 11-9 with a 2.94 ERA in a team-high 156 innings. Although ace Shohei Otani got off to a slow start and was sidelined by a blister on his pitching hand in July, the league’s top pitcher from 2015 finished the season with a 10-4 record and a 1.86 ERA.

The right-hander, whose fastball has touched a Japan-record 164 kph this season, led the team with 174 strikeouts in 140 innings.

The big additions were rookies Toshihiro Takanashi, Takayuki Kato, and imports Anthony Bass and Chris Martin.

Takanashi, a fourth-round pick in 2013 who threw 7⅓ innings last season, is 10-2 with a 2.38 ERA, while Kato, the Fighters’ second-round pick last autumn, was 7-3 with a 3.45 ERA.

“Takanashi was huge for us,” Yoshii said.

Yoshii oversaw shifts in pitching staff roles that have worked like a charm, shifting Takanashi, Kato and ineffective reliever Hirotoshi Masui to the starting rotation, and moving Bass to the bullpen, where he has been much more effective. When Masui faltered as the team’s closer, the Fighters moved Martin into that role and the right-hander earned a spot on the PL All-Star team.

“I was fortunate to step into a good situation and have everything work out. Just lucky,” Yoshii said Tuesday.

“We had a plan before the season to make those moves, but never thought it would be the story for us.”

As the club inched toward the pennant, Martin rolled his ankle and was deactivated on Sept. 4. Since then the Fighters have used a committee to close out games.

“I didn’t have any worries about that (losing Martin),” Yoshii said. “We have veterans (Naoki) Miyanishi, (Keisuke) Tanimoto, (Yuya ‘Silent K’) Ishii, in our bullpen. They are guys you can put out there and not worry about.”

Fellow pitching coach Tomohiro “Johnny” Kuroki, who oversees the bullpen, said a key factor is the camaraderie among the pitching staff.

“They’ve had this going for the past two, three years,” Kuroki said. “As we approached clinching the pennant, they were motivated to get it out of the way. There has been no taking it easy. The players do the hard work and create a good working environment for each other.

“They make my job easy.”

The pitchers’ jobs were in turn made easier by the defense making more and better plays.

“It’s been fun watching these guys work hard and make the plays they’ve been making all season,” Bass said. “Everyone’s doing their job.”