PARIS - Arsenal and Chelsea are among the sides looking to claim one of five remaining places in the last 16 of the UEFA Champions League on Wednesday's final round of group matches.

The pressure is on Jose Mourinho and his Chelsea players to avoid an early exit in Europe, even more so after the Blues were condemned to a stunning 1-0 home loss against Bournemouth at the weekend which left them just two points clear of the drop zone. Chelsea go into their final group game top of the pile on 10 points, level with Porto, and will go through as group winners with a victory while a draw would see them advance as runners-up. "It's an important week for us. On Wednesday we have to win to make sure we are first and qualified. That will be a big boost for the team as well," said goalkeeper Thibaut Courtois, who returned to the line-up at the weekend after three months out. Porto's setback against Dynamo Kiev on matchday five has left the Portuguese requiring a win to guarantee qualification. A draw could also be enough to go through, in first as well, but only if Kiev don't win.

Arsenal's qualification hopes rest on a knife edge with the Gunners knowing they have to beat Olympiakos -- either by two goals or by scoring at least three times -- to pip the Greeks to second place. Arsene Wenger's men are bidding to reach the last 16 for the 16th straight season but the injuries continue to pile up for the Premier League outfit with midfielder Santi Cazorla ruled out for up to four months with a knee injury. However, Aaron Ramsey, who scored a late third in Saturday's 3-1 win over Sunderland, is confident Arsenal can keep their streak intact. "It was never easy after the start (to the group) we had but we have done well to come back into the position that we find ourselves in and it is in our hands -- we know what we have to do," the Welshman told the club's website.

Bayer Leverkusen need to beat runaway group winners Barcelona to stand any chance of advancing to the last 16. The Germans would then still need Roma to drop points against BATE Borisov in the group's other game to reach the knockout rounds. Despite a 6-1 thrashing at the hands of Barcelona a fortnight ago, Roma remain in pole position to snatch second place in Group E. Rudi Garcia's men are level on five points with Bayer Leverkusen but own the head-to-head advantage, meaning a victory over BATE Borisov would send the Italians through to the knockout phase.

There is little at stake in Dinamo Zagreb's final-day clash against German champions Bayern Munich, but the Croatian side should brace themselves for a potential Bayern backlash in the wake of Saturday's 3-1 defeat at Borussia Moenchengladbach. Dynamo Kiev's shock win in Portugal last time out means the Ukrainian side can progress to the last 16 for the first time since the 1999-2000 season with a victory over pointless Maccabi Tel-Aviv. Dynamo could even finish as group winners if Chelsea and Porto draw. However, anything less than three points would send Dynamo into the Europa League.

Incoming Valencia boss Gary Neville will have little time to settle into his new role as the Spaniards need to beat Lyon to stand any chance of overhauling Gent for second place. Former England and Manchester United right-back Neville held his first training session on Monday, two days after Valencia held Barcelona to a creditable 1-1 draw in La Liga, and there is little margin for error against crisis-hit Lyon.

Belgian champions Gent can seal their place in the last 16 with a victory over group winners Zenit, who boast the only perfect record in this year's competition. Successive wins over Valencia and Lyon have catapulted newcomers Gent into second and they will prolong their Champions League adventure so long as they match Valencia's result against Lyon. Gent fell from the top of the Belgian league after a 2-2 draw with Zulte-Waregem on Friday but are aiming to become the first Belgian side to make it as far as the last 16 since Anderlecht in 2000-01.