Angels, who beat A’s, 12-1, could go shopping in Japan for a pitcher

OAKLAND — The Angels’ pursuit of pitching this winter will likely extend to the Far East, where a significant rotation boost could be acquired without having to trade players such as Mark Trumbo or Howie Kendrick.

The Angels, who beat the Oakland Athletics, 12-1, Monday night, had a scout in Japan last week to watch Masahiro Tanaka pitch, and they are considering a run at the undefeated Rakuten Eagles right-hander, whom scouts project as a No. 2 or No. 3 starter in the major leagues.

The 6-foot-2, 215-pound Tanaka, who features a 94-mph fastball, sharp slider and a superb split-fingered fastball, won’t come cheap. If the Eagles, as expected, post Tanaka, it could cost a major league team $25 million or more just to obtain the rights to negotiate a deal with him.

Tanaka, 24, could be worth it. Two scouts who have seen Tanaka pitch but are not authorized to speak publicly about him said that although Tanaka might not be in Texas ace Yu Darvish’s class, he could be as good as or better than Hiroki Kuroda, who is 68-68 with a 3.37 earned-run average in six big league seasons.

“I don’t think he has the creativity and the multiple weapons of Darvish, but Kuroda is a really good comparison,” one scout said. “He has three good pitches, and his splitter is a legitimate out pitch.”

Tanaka is 21-0 with a 1.24 ERA, 155 strikeouts and 27 walks in 181 innings. With such a thin free-agent pitching class, he could be an attractive option for teams.

A potential change to the posting system could add intrigue to his pursuit. Under the current system, the team that submits the highest sealed bid earns the right to negotiate with a player.

But Newsday reported Monday that the process could be changed to where the player can choose the team he wants to negotiate with from the top three bids.

On a roll

C.J. Wilson set a career high with his 17th win Monday night in Oakland, giving up one run and four hits, striking out six and walking three in seven innings to lead the Angels to their 18th win in 24 games since Aug. 23.

The left-hander is 9-0 in his last 13 starts, 13-1 with a 2.91 ERA in 17 starts since June 14 and 17-6 with a 3.36 ERA this season.

Mike Trout, Mark Trumbo and Kole Calhoun knocked in three runs apiece, Trout ending a skid at 0 for 12 with a run-scoring double and a two-run home run, his 23rd, Trumbo hitting a two-run home run, his 34th, and a run-scoring fielder’s choice, and Calhoun hitting a run-scoring single and a two-run single.

Calhoun has 23 RBIs in his last 22 games, and Trumbo has five home runs, four doubles and 14 RBIs in his last 13 games. The Angels, who pulled to within 81/2 games of the second wild-card spot with 12 games left, broke the game open with five runs in the fifth, and Trout and Trumbo homered in the eighth.

Tommy Hanson returns

Tommy Hanson returned after a humbling one-month stint at triple A, where he “simplified” his delivery but hardly solidified his future with the Angels.

“The game he came back from the disabled list, his stuff was eye-opening, and he hasn’t repeated it,” Manager Mike Scioscia said, referring to Hanson’s 51/33-inning, one-run, four-hit, eight-strikeout effort July 23.

“There are things he’s gotten more consistent with, but his last couple starts with us and at triple A were not where he was that one outing, so there’s still room for improvement.”

Hanson, 4-3 with a 5.59 ERA when he was demoted Aug. 12, was 0-2 with a 5.49 ERA in four starts at Salt Lake. He gave up one run and four hits in 61/3 innings of a playoff loss to Omaha on Wednesday.

Hanson, who is being paid $3.725 million, is eligible for arbitration this off-season, but the Angels are not expected to tender him a contract.

“I’m not worried about that now,” Hanson said. “All I can control is what I do today.”

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna