The Blues meet the Swiss champions at St Jakob-Park on Thursday and Benitez has made it clear he will not underestimate the players Murat Yakin has at his disposal.
"Basel is in the semi-final and deserve to be there," said Benitez.
"They've worked very hard, have played well, and are well organised. They press well and launch good counter-attacks.
"They have good players with pace and ability, so we will have to do really well if we want to win.
"Philipp Degen was my player (at Liverpool) and is a good professional, a worker who enjoys playing football. They have some good young players and others with more experience."