Millwall manager Kenny Jackett has described his side's 3-0 win over Luton Town in the FA Cup fifth round as a "big achievement".
The Lions eased past their non-league opponents at Kenilworth Road on Saturday to book their place in the quarter-finals of the competition.
"It's a big achievement by the players and we want to continue," Jackett told ESPN. "Scoring the first goal was the key."
The draw for the FA Cup quarter-finals takes place on Sunday.