No. 2 seed Roger Federer and No. 3 Rafael Nadal play on Friday in a must-see semifinal at Wimbledon. Nadal is a -130 favorite, with Federer listed at +110. On the game spread, Nadal is favored by 1.5. You can bet Nadal to win in straight sets at +350 or Federer to win in straight sets at +500, among many wagering options. The must-see match begins around 10 a.m. ET from Centre Court at the All England Club.

Before you make any bets, you NEED to see who Sean Calvert picked. The British tennis insider took down a huge score in March on Dominic Thiem winning Indian Wells at 80-1 and followed up last month by calling Adrian Mannarino's Libema Open title at 25-1.

The Libema Open is a grass court event like Wimbledon -- a surface Calvert knows better than anyone. Not only did he call Andy Murray's 2016 and 2013 Wimbledon championships, but anyone who has followed Calvert's grass court picks is up nearly $4,400 over the past six years!

Moreover, for Wednesday's quarterfinals, Calvert told readers to bet Federer at +230 to defeat Kei Nishikori three sets to one, and that's exactly what happened.

Now, Calvert has broken down Nadal-Federer from every angle. He's confident he has the Nadal vs. Federer winner, and he's also going BIG on multiple prop bets. As a bonus, Calvert is including his recommended bets for the other semifinal pitting Novak Djokovic vs. Roberto Bautista Agut. You ABSOLUTELY need to see his in-depth picks and analysis before you make any of your own!

Who wins Nadal vs. Federer? And what are the best bets for this must-see match? ... Join SportsLine right now to see Sean Calvert's detailed Wimbledon semifinal picks, all from the British tennis expert who specializes in grass-court events! -- Use promo code TENNIS to get your first month of SportsLine for only a buck!