The 2019 French Open continues on Friday and it features a men's semifinal matchup with a championship feel that is sure to steal the show as legends Roger Federer and Rafael Nadal go head-to-head at 6:50 a.m. ET. Nadal is the most dominant clay-court player of all time, with 11 championships at Roland Garros. He's also 5-0 against Federer in the French Open. However, Federer has won 20 Grand Slams and, at 37, he's hungry for the elusive win over Nadal at Roland Garros to further cement his legacy as one of the greatest ever. Of course, it's going to be an uphill climb and that why Federer is the +540 (risk $100 to win $540) underdog with Nadal at -750 (risk $750 to win $100) in the latest Nadal vs. Federer odds. The over-under on sets is 3.5, the over-under on games is 27, and Nadal is favored by 6.5 games overall. But before you make your Federer vs. Nadal picks, be sure to check out the 2019 French Open picks and predictions from SportsLine tennis expert Sean Calvert first.

An internationally-acclaimed tennis journalist, Calvert is crushing the 2019 French Open. He predicted Nadal would destroy Nishikori, recommending Nadal -9.5 games and their second set to last fewer than 8.5 games. The result? Nadal breezed to a 6-1, 6-1, 6-3 victory, handing two easy cashes to anyone who followed Calvert's advice. Calvert also said Federer would take care of Wawrinka, and that's exactly what happened.

It's no surprise, as Calvert has been cashing consistently for six years. Among his legendary calls: Dominic Thiem to win Indian Wells this year at 80-1, Jack Sock to win the 2017 Paris Masters at 80-1, and Wawrinka to win the 2014 Australian Open at 60-1.

Now, Calvert has broken down Federer vs. Nadal, combining detailed statistical analysis and his years covering the sport to produce three best bets on this titanic matchup. Two of the picks are plus-money bets, with one paying out at 2.5-1. He's sharing them over at SportsLine.

Calvert knows that Nadal is as close to unbeatable on clay as anyone has ever been. And he has a particular affinity for Roland Garros, where he has an astonishing 91-2 record in his career. The 17-time Grand Slam champion with 81 career victories (fourth most in the open era) has won 11 French Open titles in the last 14 years.

He's the current world No. 2, and at 33, is still dominating at the French Open. It's not inconceivable that he could surpass Federer's 20 Grand Slam titles if he can get past his long-time rival again on Friday morning. Look for Nadal to use his quickness and his footwork per usual on Friday to try to get the upper hand against Federer.

But just because history is on his side doesn't necessarily mean that Nadal is the best value pick in this French Open 2019 men's semifinal matchup.

It's worth noting, Calvert said, that Nadal and Federer haven't faced each other on clay "since way back in 2013 in Rome and prior to that in 2011 here at the French Open, when Nadal won in four sets -- three of them very tight."

Federer will be fresh given the long break between matches, and "in the past, he has created enough break chances on clay against Nadal (0.60 per game)," Calvert added. Federer also has won the past five matchups against Nadal, though all of those came on hard courts.

Calvert has taken into account all of these factors, and many more you haven't thought of. Not only is he confident he has the winner, but he's betting on how long the match lasts, how long the first set lasts and how many games one player wins.

Who wins Federer vs. Nadal? And exactly how long does the match last? Visit SportsLine now to see Sean Calvert's three best bets on Nadal vs. Federer, all from the uncanny expert who's crushing his 2019 French Open picks.