El-Hadji Diouf put Bolton in sight of the UEFA Cup last 16 by snatching a late 1-0 first-leg win over Atletico Madrid.
The Senegal forward left Ghana early after his side failed to make their expected impact at the African Nations Cup.
But the smile was back on his face at the Reebok Stadium as he gave the Trotters a slim advantage going into the second leg of the round of 32 in Spain next week after good work by Stelios Giannakopoulos and Matt Taylor.
Diouf scored the winner in the 74th minute, 60 seconds after Atletico substitute Sergio Aguero was sent off, apparently for spitting.
Gary Megson's men richly deserved the victory and Taylor was outstanding, with the former Portsmouth midfielder going close on several occasions and running the visitors ragged all evening.
The La Liga club tried hard to get back in the game but Wanderers held on.