Canadians Denis Shapovalov and Gabriel Diallo dropped their opening men’s singles matches Monday at the Monte Carlo Masters tennis tournament.

Belgian Alexander Blockx defeated Shapovalov, of Richmond Hill, Ont., 6-4, 4-6, 6-3. Both players had two aces, but the Canadian recorded more than twice as many double faults (five) as Blockx (two).

Blockx also converted on three of four breaks in the match while Shapovalov was two-of-seven.

Meanwhile, Joao Fonseca of Brazil dispatched Diallo, of Montreal, in straight sets 6-2, 6-3. Fonseca only had two aces but no service faults, while Diallo double-faulted four times to go with his lone ace.

Fonseca also earned five service breaks in eight tries while Diallo converted just once in his four attempts.