(CNN) -- Zenit St.Petersburg slipped up in their defense of their defense of the UEFA Cup as the Russian side went down 2-0 to Udinese on Thursday night.
Midfield action from the Udinese - Zenit tie which saw the holders beaten 2-0.
Fabio Quagliarella and Antonio Di Natale scored in the last five minutes for the Serie A side in the first leg of their last 16 tie.
Quagliarella grabbed his fifth goal of this year's competition to put Udinese ahead with Di Natale scoring from the spot in injury time.
Zenit defender Roman Shirokov was sent off for a second yellow card in conceding the penalty.
Dick Advocaat's men now face an uphill task in the second leg next week if they are to reach the quarterfinals.
The other standout last 16 tie saw Marseille beat Ajax Amsterdam 2-1 in a battle of former European champions.
Benoit Cheyrou and Mamadou Niang scored to put the French side ahead in their home tie before Luis Suarez hit back for the Dutch visitors with a 36th minute penalty.
Bundesliga title challengers SV Hamburg were held to a disappointing 1-1 home draw by Turkish side Galatasaray.
Ayhan Akman put the visitors ahead in the 33rd minute before Marcell Jansen equalized for Martin Jol's men five minutes into the second half.
Galatasaray had to play most of the second half with 10 men after Emre Asik was sent off but held out.
French title challengers Paris St.Germain were held scoreless by Portuguese visitors Braga, while Dynamo Kiev beat fellow Ukrainian side Metalist Kharkiv 1-0 after a 54th-minute goal by Ognjen Vukojevic.
Brazilian Vagner Love scored a 50th-minute penalty to give CSKA Moscow a 1-0 win over Shakhtar Donetsk, while Werder Bremen, who put out AC Milan in the previous round, scraped home 1-0 in their home tie against Saint Etienne through a 20th-minute goal by defender Naldo.