As the remaining players in the draw fight for a spot in the final, we preview and predict three must-see matches in Key Biscayne.

Halep, a semifinalist here last year, has looked dialed in so far in Miami, determined to get her season moving in the right direction after a slow start. So far she’s beaten Daria Kasatkina, Julia Goerges and Heather Watson, all in straight sets, and has hit the ball with more pace and purpose than she has anywhere else this year. Now that she's the highest seed left in the top half of the draw, Halep should, if anything, be more determined—with Serena Williams out, a big title is suddenly within her grasp. But while Halep has beaten Bacsinszky in straight sets in their two previous meetings, the Swiss finally appears ready to turn her own disappointing season around—she has beaten Ana Ivanovic and Agnieszka Radwanska in her last two matches. Bacsinszky and her backhand could do the same on Tuesday, but the percentages are with Halep. Only one turnaround at a time.

Winner: Halep

This may be the most relevant matchup of the first quarter of 2016: Djokovic has won the Australian Open and Indian Wells, while Thiem won two tournaments in between. While the 28-year-old Serb is the ATP’s present, many of us believe that the 22-year-old Austrian is the closest thing we’ve seen to its future. And while Djokovic is the two-time defending champion in Miami, Thiem made a breakthrough by reaching the quarters here last year. So despite the fact that Djokovic is a five-time winner on these courts, Thiem should also feel comfortable on them, and have time to take the huge topspin cuts for which he’s fast becoming famous. They’ve played once, on a quicker court in Shanghai two years ago, and Djokovic won, 6-3, 6-4. I’m thinking Thiem connects often enough to win one set this time, but not two.

Winner: Djokovic

Over the first week, Miami has mostly been about surprising failures—Rafael Nadal’s, Serena Williams’, Andy Murray’s. Dimitrov and Monfils have been among the surprising successes. That’s good news for fans of flashy shot-making: It’s hard to think of two more exciting talents. It’s also hard to think of two more frustrating talents. Neither has come close to fulfilling his so far, but both have shown signs of a new seriousness in 2016. Can Monfils keep his game face on for another day? Can Dimitrov bounce back 24 hours after a win over Murray? If the answer is yes to both, this could be a display to remember. Monfils leads their head to head 3-1.

Winner: Dimitrov