Before each day of play at Roland Garros, we'll preview and predict three must-see matches.

These two played a famous first-round epic at Wimbledon five years ago, in which Federer, the defending champion, came back from two sets down to win. They’ve faced off twice since, both times on grass, and Falla has acquitted himself well both times in defeat. Oddly, Federer has had an easier time with the Colombian lefty on clay. They played at the French Open in 2006 and 2010, and Federer won in straight sets on each occasion. If anything, he’s even farther ahead of the 31-year-old Falla, who’s currently ranked No. 111, now than he was then. Winner: Federer

On the surface, this looks like a typically one-sided first-rounder involving a high seed. Nishikori is ranked No. 5; Mathieu is ranked No. 123. Nishikori is 25 and in his prime; Mathieu is 33 and well past his. Nishikori tuned up for the French Open by reaching the semis and the quarters at Masters events in Madrid and Rome, respectively; Mathieu did his Roland Garros preparation at Challengers in Aix en Provence and Bordeaux. But Mathieu reached the final in Aix en Provence, and three years ago he rose from the near-dead at Roland Garros to beat John Isner 18-16 in the fifth. The fans in Lenglen will be pulling for a repeat against Nishikori, who went out in the first round in Paris last year. They should be able to get their man a set. Winner: Nishikori

Is this worth putting on upset alert? Ivanovic has spent 2015 in borderline free fall, reaching the quarters in just two of nine events and suffering three first-round losses, including one last week in Rome. Shvedova is ranked just 65th and is mired in the qualifying at most events these days, but she’s an athletic two-time quarterfinalist at Roland Garros who nearly beat Serena Williams at Wimbledon three years ago. Ivanovic and Shvedova split the two matches they’ve played. Winner: Ivanovic​

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