Ghana striker Asamoah Gyan registered 19 league goals in the UAE top-flight after a double on Sunday helped ten-man Al Ain thump Emirates 4-1.
Gyan opened the scoring on seven minutes and added a second in the 23rd minute.
But Al Ain were forced to play with ten men after Radoi was sent off for a last man foul on Alexander Geynrikh on the half hour mark.
Geynrikh reduced the arrears for the hosts, but one of UAE star Omar Abdulrahman restored the two goal lead going into the break.
Argentine Ignacio Scocco hammered the final nail into Emirates coffin soon after the restart.
Al Ain won the Etisalat Pro League last week with three matches to spare.