Unbeaten in nine home matches in European competitions, CSKA Sofia faced a tough opposition in the form of FC Basel on October 22 2009, and were comfortably outplayed as Alexander Frei scored a brace, one in each half to propel the visitors on top of Group E.
 
The visitors were menacing on most occasions when they surged forward. The atmosphere at Vassil Levski stadium generated by the red supporters was not going to intimidate them in any way and Basel quickly obtained the initiative on the pitch.
 
Just 19 minutes into the first half and CSKA Sofia were 1-0 down when Marco Streller allowed a long pass bound for him to reach Frei, who in turn chested the ball and drove it past the advancing Ivan Karadzhov.
 
CSKA Sofia were then lucky not to concede a second four minutes from time when the Switzerland forward burst through in the penalty area in the 41st minute, beating two defenders, and having done the difficult part of the task, managed to squander it all by shooting wide off the post from several metres.
 
Second half under way, and the visitors maintained their harassment in style. It was a selfless and desperate defence from substitute Aleksandar Branekov that denied Frei from scoring a second goal on the stroke of the hour mark.
 
It was apparent, however, that the second goal was only a matter of when and not if, and it did not come too long afterward. Frei rose to meet Carlitos's cross from the right with a header in the 64^th minute, making it a brace for himself and a comfortable 2-0 away win for his team.
 
The victory over CSKA left FC Basel with six points in the bag, one more than Fulham and two clear of AS Roma, while CSKA are five adrift. This defeat was the first time CSKA lost a European match at home since the 1-0 defeat inflicted by Hamburger SV in October 2005.