The Wellington Phoenix have surrendered the A-League's only unbeaten run, losing 3-1 to Adelaide United after some poor officiating.
Stein Huysegems produced his third goal in four games, but Cassio and two goals from Jeronimo Neumann gave Adelaide the points.
Cassio's goal, which put Adelaide 2-1 up, should not have stood however.
After a 50-metre run, the Brazilian played a one-two with Neumann on the edge of the Phoenix penalty area - but when Neumann played the ball back, Cassio had strayed into an offside position.
Cassio stroked home past Mark Paston but none of the officials managed to spot the infringement and allowed the winner to stand.
Rubbing salt into the wound, referee Jarred Gillett reinforced the error in 77th minute when he gave Ben Sigmund a straight red card.
Sigmund was tracking Neumann back to goal and while the New Zealander made contact with the striker's arm, Neumann remained on his feet and then fell to the ground two paces later as the ball slipped out of his possession.
Phoenix captain Andrew Durante was furious at full time, blasting the officiating as "shocking" and Neumann a "cheat".
Adelaide couldn't capitalise on the resulting free-kick from Neumann's dive, but Neumann put the game beyond doubt in the 85th minute when he linked with Dario Vidosic and pulled apart a 10-man Phoenix.
- Fairfax Media
Who will win this year's Champions League?