Denis Shapovalov lost his first match of the 2019 tennis season as Joao Sousa came from a set down to advance to the second round of the ASB Classic in Auckland.
The Canadian No. 7 seed, who enjoyed a breakthrough year in 2018, looked comfortable as he broke Sousa twice to win the opening set 6-4.
Sousa responded to take a 4-1 lead in the second, holding serve in the final game of the set to win 6-4 and level the match. The Portuguese then sealed the only break of serve in the decider to win in two hours, 22 minutes.
Sousa, who won the tournament in 2017, will face Cameron Norrie in the second round after the Brit defeated Benoit Paire 6-3, 6-2 in just 58 minutes.
American Taylor Fritz also recovered from a set down to defeat Marius Copil 4-6, 6-3, 6-4. The world No. 50 fired 12 aces as he set up a meeting with compatriot and No. 1 seed John Isner.
Meanwhile, former Auckland champion Philipp Kohlschreiber defeated U.S. qualifier Bradley Klahn 6-4, 7-6(2), the 11th time he had won his opening match at the ASB Classic.
Matteo Berrettini defeated another U.S. qualifier in Mackenzie McDonald 6-3, 6-4, setting up a second-round clash with German Maximilian Marterer who defeated Tennys Sandgren 6-3, 6-4, while Jan-Lennard Struff advanced after Serbian opponent Laslo Djere retired in the second set with the German leading 7-6 (5), 2-0.