MADRID, Feb. 20 (Xinhua) -- Four Spanish clubs are in Europa League action on Wednesday and Thursday night with all of them favorites to make it through to the last 16 of the competition after good results in their first leg ties.

Sevilla may have been struggling domestically with two defeats and a draw in their last three Liga Santander matches, but a 1-0 win in Rome last week gives them the advantage when Lazio visit the Sanchez Pizjuan on Wednesday night.

Police in Seville are on high alert after a fight last week in Italy before supporters of both clubs injured. The main reason the game is being played on Wednesday is that Sevilla's neighbors and local rivals Betis entertain Rennes on Thursday and authorities don't want four sets of fans in the city at the same time.

Last week saw Betis fight back from 3-1 down to claim a 3-3 draw in Rennes and they will be favorites to qualify, although their recent league form has been shaky and the efforts of also reaching the semifinals of the Copa del Rey appear to have taken their toll on Quique Setien's players.

Valencia should have a relatively easy home game against Celtic after a 2-0 win in Glasgow last week.

The two goal cushion should easily be enough to see Valencia into the last 16, a week before they play Betis in the second leg of their Cup semifinal.

Once again security could be an issue surrounding this game with the British Embassy in Madrid asking Celtic fans not to travel to Valencia without tickets.

Finally the return to Europe brought good news to Villarreal, who won 1-0 away to Sporting Lisbon and followed that up with a 3-0 thrashing of Sevilla at the weekend. With his side still in the relegation zone, Villarreal coach Javi Calleja needs to balance domestic and European requirements, but the boost to morale after the past two wins could be vital to Villarreal's top-flight survival.