British number one Cameron Norrie secured his third ATP Tour title with victory over Reilly Opelka in the final of the Delray Beach Open.

Norrie edged a hard-fought contest 7-6 (1) 7-6 (4) against his big-serving American opponent, who sent down 25 aces but was unable to threaten Norrie’s serve.

The top seed failed to take any of the five break points he created against Opelka, who had needed three hours to win his third consecutive three-set match against John Millman in the semi-finals.

But Norrie raced through the first set tie-break and won the crucial points in the second set tie-break as well, most notably edging 5-4 ahead when Opelka’s forehand pass flew agonisingly long.

Norrie, who lost just one set on his way to the title, told the ATP’s website: “I thought I played a very clean match.

“I didn’t face a break point so that was great. I was happy with the way I played and obviously with the result.

“The tie-breaks I played extremely aggressively, the second one especially. I managed to put a couple of balls away and I was reading the play great. I’m super happy to get the win and beat a guy like Reilly, who is confident and playing well and won (in Dallas) last week.”

Spain’s Carlos Alcaraz became the youngest ATP 500 champion since the category was created in 2009 with victory in the Rio Open.

The 18-year-old defeated third seed Diego Schwartzman 6-4 6-2 to win the second tour-level title of his career.

“I can’t believe it, honestly. It has been a great week for me playing a great level,” Alcaraz said in his on-court interview.

“First tournament on clay since a long time, so I’m really happy with the performance during the whole week. It’s an amazing feeling right now.”