Giovanni Mpetshi Perricard has completed a perfect week on serve by upsetting American Ben Shelton to win the Swiss Indoors title in Basel.

The 21-year-old Frenchman, ranked No.50, prevailed 6-4 7-6 (7-4) against Shelton to become the lowest-ranked champion since the tournament became a tour-level event in 1975.

Mpetshi Perricard did not drop serve all week in Basel, winning all 60 of his service games and having to fend off just three break points — all in his quarter-final against Denis Shapovalov.

He also served up 22 aces against Shelton on his way to taking his first ATP 500 trophy.

"It's amazing to win a tournament like that. A 500 for the first time for me," Mpetshi Perricard said.

"I just can be happy with myself, with what I did today and the past five days.

"It's amazing to win here. Before this, it was a tough month for me, but it's always good when the victories are there."

Mpetshi Perricard started the year ranked 200, won several Challenger titles and his first ATP crown in Lyon in May. He'll now rise to career-high ranking of 31 on Monday.

Shelton's run this week has also guaranteed the young American's return to the top 20 from No.23.