Souza upsets Haase in Sao Paulo first round
Souza broke Haase late in each set, serving to close out the match for his first win of the year. Haase, ranked 45th, had four chances to break the Brazilian's serve, but couldn't capitalize on them.
Mayer, served 11 aces and had five break opportunities in the final set while Pella had one, but each player broke each other only once.
Tommy Hass of Germany is the tournament's top seed.