Shawn Tolleson is knocking on Dodgers’ door

Reporting from Phoenix -- There was a time when Clayton Kershaw used to look at one of his best friends and wonder, “What if …?”

No more.

The Dodgers’ minor league pitcher of the year, Shawn Tolleson, is only a step away from the major leagues.

“It worked out,” Kershaw said.

With the Dodgers opening a season-ending three-game series against the Arizona Diamondbacks at Chase Field on Monday, Kershaw’s childhood friend was about 20 miles away at the team’s spring training complex, refining a changeup in the instructional league.

For most of their teenage years, Kershaw and Tolleson were teammates on a travel club in their native Texas that also included Jordan Walden of the Angels.

“He was the best high school pitcher in the area,” Kershaw said of Tolleson.

That changed when Tolleson blew out his elbow in the first start of his senior season.

“It was one random pitch in the third inning,” Tolleson said. “It kind of popped. I knew right away.”

Later that year, the Dodgers selected Kershaw with the seventh overall pick of the amateur draft. Tolleson went to Baylor University, where he sat out his freshman year recovering from Tommy John surgery.

“I felt for him so bad,” Kershaw said.

A three-year starter at Baylor, Tolleson was moved into the bullpen after the Dodgers selected him with their 30th-round pick of the 2010 draft.

Tolleson’s rise has been meteoric.

Last season, he posted a 0.63 earned-run average in 26 appearances for rookie-level Ogden. This year, he was a combined 7-2 with 25 saves and a 1.17 ERA in 57 appearances between low-A Great Lakes, high-A Rancho Cucamonga and double-A Chattanooga. The 23-year-old right-hander averaged 13.7 strikeouts per nine innings.

If not for his arm trouble, Kershaw said Tolleson would be in the big leagues by now.

“I have no doubt in my mind he would be in this clubhouse, if not another one,” Kershaw said.

Tolleson said he doesn’t think about that too much, adding that he draws strength from watching his friend.

“Seeing him succeed is fun for me,” Tolleson said. “It’s a good feeling. It motivates me.”

As they did last winter, Kershaw and Tolleson plan to work out together in the Dallas area this off-season. Next year, they could share the same clubhouse.

“I’m looking forward to it,” Kershaw said.

Hiroki Kuroda to make last start

Hiroki Kuroda is heading into his final start of the season only four innings shy of the 200-inning mark, and a $200,000 bonus.

Kuroda finished last season with 1961/3 innings, as he declined the opportunity to take his final turn in the rotation. That’s something the 36-year-old said he now regrets.

“Looking back, I should have done it,” he said. “To pitch 200 innings in back-to-back seasons would have been something, especially at this age.”

Kuroda, 36, will be a free agent this winter. He said he hasn’t decided whether he will pitch in the major leagues next season or return to his native Japan.

Russell Mitchell to have surgery

Rookie utilityman Russell Mitchell will undergo arthroscopic surgery on his left wrist Tuesday. Mitchell has had torn cartilage in the wrist since late spring, trainer Stan Conte said. With his recovery expected to take six to eight weeks, Mitchell should be able to play in the Venezuelan winter league, as was previously planned.

dylan.hernandez@latimes.com