Jessica Pegula, the fifth seed, was stunned by Australian Kimberly Birrell, 1-6, 6-3, 6-3 after routing her opponent in the first set.

But earlier, there was arguably an even bigger shock.

Russian Daniil Medvedev (6), his Roland Garros issues notwithstanding, was knocked out by Australian wildcard Adam Walton, ranked No. 97 in the world.

Walton took the match 6-2, 1-6, 6-1, 1-6, 6-4 on the red clay to move into the second round.

Here’s hoping for some similarly interesting results today.