Girondins Bordeaux are on course to reach the Champions League quarter-finals for the first time after Michael Ciani's first-half header earned Laurent Blanc's side a 1-0 victory at Olympiakos Piraeus.
Bordeaux, who amassed more points than any other team in the group stage, soaked up late pressure and were good value for a last 16 first-leg win that makes them favourites to progress ahead of the return at the Stade Chaban-Delmas on March 17.
"We played very well. We came to show we are serious competitors in this competition and we displayed this during the course of the match," Blanc said, after Ciani's winner in added time at the end of the first period.
"We scored a goal at an important point. In the second half we left too much space for Olympiakos and there were spells when I felt we could have been more aggressive but in general I am satisfied," added Blanc.
"We came here in order to see what our chances were of progressing and with this result we have increased our chances of reaching the quarter-finals."
Olympiakos had booked their place in the last 16 by finishing second in Group H thanks largely to their home form and, roared on by a typically passionate crowd, began strongly.
However, the home side's best chance of the game came with just under 10 minutes left when former English Premier League forwards Matt Derbyshire, on as a second half substitute, and Lua Lua combined but the latter saw his shot tipped around the post.
The hosts, who were playing in their 200th European game, also had a goal chalked off in the closing seconds.
"I consider that we were very good today," said Olympiakos coach Bozidar Bantovic.
"If we play like we did today we have nothing to fear in France."