Michelsen reaches Newport ATP semi-finals

American Alex Michelsen continued his breakthrough run at the ATP grass court tournament in Newport, Rhode Island on Friday, downing Mackenzie McDonald to reach his first tour-level semi-final.

The 18-year-old Californian, who beat defending champion Maxime Cressy earlier this week, beat McDonald 6-3, 6-3 to line up a final-four clash with veteran John Isner.

Michelsen, ranked 190th in the world, dominated on serve in the opening set and closed out the match in one hour and 11 minutes.

"I served really well, first-serve percentage was probably pretty high," Michelsen said. "The serve was key today and I didn't miss too many groundstrokes either, so that was nice."

Isner, a four-time Newport winner, overcame a slow start to beat 14th-ranked Tommy Paul, the top seed, 4-6, 6-3, 7-6 (7/4).

At 38, he'll be giving up 20 years to his semi-final opponent, who has committed to playing for the University of Georgia -- where Isner graduated in 2007.

The other semi-final was set on Thursday, when second-seeded Adrian Mannarino beat Australian Jordan Thompson to set up an all-French clash with Ugo Humbert, a straight-sets winner over South African Kevin Anderson.