Gabriel Diallo to face 4th seed Ben Shelton in Citi Open 3rd round after straight-sets win

Montreal's Gabriel Diallo advanced to the third round of the Citi Open hard-court tennis tournament with a 6-3, 6-4 win over Hungary's Fabian Marozsan on Tuesday in Washington.

Diallo, who had a first-round bye as the 15th seed in Washington, had 10 aces and broke Marozsan twice on seven chances.

Marozsan, who committed six double faults, failed to convert the only chance he had to break Diallo's serve.

Diallo improved to 2-0 against Marozsan, with his other win coming earlier this year in a Davis Cup qualifier.

Diallo will play on Thursday against the fourth-seeded Ben Shelton, who beat wild card Mackenzie McDonald 6-3, 6-4 in an all-American matchup on Tuesday.

Diallo, who entered the tournament with a career-high world ranking of No. 35, is seeded 30th at the men's National Bank Open in Toronto. The Masters-level event starts with qualifying on Saturday.

WATCH | Diallo edged by No. 5 Fritz in Wimbledon 2nd round:

Montreal's Gabriel Diallo drops 5-set heartbreaker at Wimbledon