Miami - Canadian top seed Milos Raonic advanced to the quarter-finals of the ATP Delray Beach Open on Wednesday by defeating Croatia's Borna Coric 6-3, 7-6 (7/2).
On a night when rain delayed the start of play for more than eight hours, world number four Raonic fired 12 aces on his way to victory after 94 minutes in the early minutes of Thursday morning.
Raonic, who reached the tie-breaker with his 11th ace and reached match point with his last ace, booked a Friday quarter-final matchup against British eighth seed Kyle Edmund, who outlasted Taiwan's Lu Yen-Hsun 6-3, 3-6, 6-2.
Also advancing to the last eight was US third seed Jack Sock, who downed Spain's Guillermo Garcia-Lopez 6-4, 6-1, and American fifth seed Steve Johnson, who eliminated Japan's Yoshihito Nishioka by the same score.
Sock and Johnson will meet in another quarter-final.
Thursday's matchups find Argentina's seventh-seeded Juan Martin Del Potro, in his first tournament of the year after helping his homeland win the Davis Cup, meeting Bosnia's Damir Dzumhur.
Two other second-round matches on Thursday will be all-American affairs, with teen star Taylor Fritz facing Donald Young and fourth-seeded defending champion Sam Querrey meeting Jared Donaldson.
Results on Wednesday from the ATP Delray Beach Open (x denotes seed):
Jack Sock (USA x3) bt Guillermo Garcia-Lopez (ESP) 6-4, 6-1
Steve Johnson (USA x5) bt Yoshihito Nishioka (JPN) 6-4, 6-1
Kyle Edmund (GBR x8) bt Lu Yen-Hsun (TPE) 6-3, 3-6, 6-2
Milos Raonic (CAN x1) bt Borna Coric (CRO) 6-3, 7-6 (7/2)