Roger Federer captured his fourth Miami Open title with an emphatic 6-1 6-4 win over defending champion John Isner.

The 37-year-old world number five broke in the opening game and took the first set in 24 minutes.

In his 50th Masters final, the Swiss fourth seed produced some typically sublime groundstrokes and wrapped up the match in an hour and three minutes.

It is his 28th Masters title and the 101st overall for a player who has won 20 Grand Slam singles titles.

Following his victory at the Dubai Championships, Federer becomes the first two-time champion on the ATP Tour this season, ending a streak of 19 different winners in 2019.

Isner came into the first meeting between the pair in Miami having not dropped a set throughout the tournament, winning nine of the 10 sets in the process by tie-break.

Federer had won all four of their previous matches on hard courts and asserted his dominance from the outset.

Seventh seed Isner had treatment on his left foot at 4-3 down in the second set but the match was soon brought to its conclusion as Federer improved his overall record against the angular, 6ft 10in (2.08m) American to six wins in eight matches.

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