Defending champion Ben Shelton shook off a nasty crash into a backcourt hoarding as he steamrolled Learner Tien 6-2, 6-3 to reach the final of the ATP Montreal Masters on Wednesday.

Shelton, who won the title in Toronto last year in the ATP Masters 1000 event that alternates between cities, will try to double up in Toronto when he takes on fellow American Brandon Nakashima in Thursday’s title match.

Nakashima held off Spanish teenager Rafael Jodar 7-6 (7/3), 6-4 to book his first ATP Masters final.

“It means a lot, so many American guys in the mix,” Shelton said.

The last all-US pair to battle for a Masters trophy were Mardy Fish and Andy Roddick in 2003 in Cincinnati.

Shelton was treated by a trainer in the second set to staunch bleeding from his left elbow and webbing of his fingers.

He shook off the discomfort to earn a payback win against Tien, who had beaten him in two previous meetings.

“I played four good return points after the timeout, I was not feeling anything except the sting of the medicine,” Shelton said.

“I’m super happy with the performance,” added the American, who saved all four break points he faced and won 81 percent of his first-serve points.

“Learner presents a lot of problems to my game. He’s a challenge to overcome,” Shelton said. “He can jerk you around the court. I had to play intelligent tennis. The final will be a war and I’ll leave it all out on the court.”

Shelton is seeking his fourth title this season after winning on three different surfaces: indoor in Dallas, clay in Munich and grass in Stuttgart.

He has beaten Nakashima all five times they have played — including in Toronto last year.

Crazy game

Nakashima needed two hours — including 66 minutes in the second set — to subdue Jodar.

The Spanish sensation, a finalist in Washington this month and tipped to soon crack the top 10 in the rankings, saved four match points before his opponent fired an ace on his fifth opportunity to prevail in a final game that featured six deuces and lasted more than 10 minutes.

“That final game was crazy,” Nakashima, 25, said. “It was super-tight. We both had to keep fighting. 

“I was lucky I was hitting my spots on serve, it paid off today. I’m happy to get through that one.”

Nakashima goes into his first Masters final with growing confidence on serve and with his forehand.

“I’m just trusting it and swinging through on every ball,” he said. “When I connect with it, (my forehand) is one of my best shots. I’m happy it paid off today.”

Nakashima will be playing the fifth final of his career and by far his most prestigious.

He has never before competed in anything more than a 250-level title match.

Jodar said he’d take “a lot of positive things” from Montreal as the build up to the start of the US Open on August 31 continues.

He said fatigue wasn’t a factor, despite piling up matches in his deep runs in Washington and Canada.

“It wasn’t about that. I was feeling good,” he said. “I was trying to play my game the whole match.

“He played especially the important points of the match better than me, and that’s one of the reasons why he won the match today.”

Swiatek downs Svitolina

Former world number one Iga Swiatek turned the tables on Elina Svitolina, outlasting the Ukrainian 6-3, 1-6, 6-3 on Wednesday to reach her first WTA final of the year in Toronto.

Swiatek, seeded seventh, improved to 5-3 against Svitolina, who had narrowed their head-to-head record with two wins over the Polish star this year.

In Thursday’s final, Swiatek will play either American fourth seed Coco Gauff or Australian Open champion Elena Rybakina of Kazakhstan, who is seeded two.

In a match delayed more than an hour by rain, Swiatek raced to a 4-0 lead in the opening set, in which Svitolina held serve just twice.

The Ukrainian made Swiatek work to serve it out, saving a pair of set points in the final game of the first.

Energized, she raced through the second set before Swiatek rebounded in the third, breaking Svitolina to love for a 5-3 lead before holding serve to secure the win.

“Against Elina it’s always tough, so I’m happy that I won this one,” said Swiatek, a six-time Grand Slam champion who will be chasing her first title since she won in Seoul almost a year ago.

“Especially that I came back in the third set playing better. So, yeah, that’s for sure a big improvement. I’m proud of myself.”