ROME (AP) -- It's going to be a rare all-American affair in the Italian Open final.

Top-ranked Serena Williams will meet 21-year-old Madison Keys on Sunday to mark the first time two American women have met in a final on clay since Serena beat older sister Venus in the 2002 French Open.

Serena beat 35th-ranked Irina-Camelia Begu 6-4, 6-1 and the 24th-ranked Keys defeated Wimbledon finalist Garbine Muguruza 7-6 (5), 6-4 Saturday after several rain delays.

The last all-American women's final in Rome was in 1970, when Billie Jean King beat Julie Heldman.

''It will be wonderful,'' Serena said. ''I feel like Madison is one of the players that really can be great and she has that potential, and now she's showing that on all surfaces.''

In the men's tournament, top-ranked Novak Djokovic and Andy Murray will meet in a final for the second straight week.

Djokovic came from behind and needed four match points to beat sixth-seeded Kei Nishikori 2-6, 6-4, 7-6 (5). Murray defeated lucky loser Lucas Pouille 6-2, 6-1.

In last week's Madrid Open final, Djokovic beat Murray in three sets.

The final will come on Murray's 29th birthday.

''I don't remember winning any matches on my birthday, which isn't a great sign,'' Murray said.

Djokovic appeared to injure his left foot during the first game against Nishikori. Attempting to knock the clay out of his shoe with his racket, the Serb hit his ankle instead and there was a deep bruise.

On the changeover, Djokovic had a trainer come out and clean the bruise but it took him until the second set to really regain his footing. Still, Nishikori wouldn't go away and fought to the end. The match lasted just more than three hours.

On the women's side, there hadn't even been two Americans in the Rome semifinals since Jennifer Capriati beat Serena in 2004.

''Madison gets better every time,'' Serena said. ''When they're young like her and the future of American tennis, it's so good to see them get better.''

Serena is 15-0 against Americans since losing to Venus in the Montreal semifinals in 2014, while her last loss to an American in a final came against Venus at Wimbledon in 2008.

''Obviously I love playing Venus in the final, because it means that we both have done the best that we can,'' Serena said. ''But outside of that ... I feel like this is the answer ... Madison and Sloane (Stephens) and all those great Americans that are doing so well. It's great. It is really, really great to see.''

The championship match will be the third meeting between Serena and Keys and will come exactly a week before the French Open begins. Serena beat Keys in straight sets in both the Australian Open semifinals and U.S. Open Round of 16 last year.

''I played her pretty close the first set of the Australian Open. So (that) definitely made me realize that I can stay in it,'' Keys said.

The 34-year-old Serena will be aiming for her 70th career title while Keys will be looking for her second.

Serena hasn't won a title since a U.S. Open tuneup in Cincinnati in August. She's a three-time Rome champion in 2002, 2013 and 2014.

While she committed one more unforced error than Begu, Serena was never really in trouble.

Keys had to overcome a five-minute suspension for rain when she was up 30-15 while serving for the match. But she maintained her composure and finished it off by winning two of the next three points.

''I was able to keep my nerves under control and serve it out and win,'' Keys said.

Keys was more aggressive, hitting 29 winners to Muguruza's 20.

The third-seeded Muguruza struggled with her serve, hitting eight double faults.

The start of the Murray-Pouille match was delayed for nearly an hour due to rain. Then there was a suspension of about 10 minutes midway through the first set due to a brief downpour.

The match time was less than an hour.

Murray, who hasn't dropped a set this week, will return to No. 2 in the rankings ahead of Roger Federer on Monday.

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