Paris: Growing in belief and confidence with each game, Arsene Wenger's Arsenal can confirm their recent resurgence by reaching the Champions League last 16 with victory at home to Marseille on Tuesday.
After a wretched start to the season, in which they won just three of their opening eight games and were humiliated 8-2 by Manchester United, Arsenal have turned their campaign around with a run of eight wins in nine matches.
The most recent of those victories was the most striking, a stunning 5-3 success at Chelsea on Saturday that thrust the Gunners back into the race for a top-four place and shattered doubts about their supposed vulnerability.
Robin van Persie was Chelsea's conqueror, netting a slickly taken hat-trick, but it is thanks to an injury-time Aaron Ramsey goal at Marseille in their last European outing that Arsenal find themselves on the brink of the last 16 in the Champions League.
The Welshman's strike at Stade Velodrome allowed his side to leapfrog OM at the Group F summit and three more points against Didier Deschamps' team on Tuesday will put Arsenal in the knockout phase for the 12th season in a row.
"What has changed is that we got half of the team in on August 31 (transfer deadline day) and we had to qualify for the Champions League," explained Wenger.
"We had to rebuild a complete unity in the way we want to play football. Every win makes you stronger as well."
"We are more consistent now and we have to keep that going. Tuesday night will be another test, where we will have to focus and produce that quality again. That's what is at stake."
Like Arsenal, Marseille struggled at the start of the season but appear to have turned a corner in recent weeks.
Saturday's 3-2 victory at promoted Dijon was the club's third victory in succession in all competitions and lifted OM up to ninth in the Ligue 1 table.
Marseille's attacking players have been liberated by a new 4-4-2 formation introduced in a 2-0 win at home to Ajaccio on October 22, but Deschamps is likely to revert to a more cautious set-up for the trip to the Emirates.
In the other Group F fixture, Borussia Dortmund host Olympiakos needing victory to keep their qualification hopes flickering.
After an unscheduled 2-1 loss at the Greek side in their previous match, the German champions are just one defeat away from elimination.
Chelsea will bid to turn the page on a damaging week with a win at Genk in Group E, which should be enough to see the 2008 finalists into the next round.
Saturday's loss to Arsenal was the first time Chelsea had conceded five goals at home in a league game since December 1989 and came amid racism allegations swirling around captain John Terry.
However, should they win in Belgium and Valencia fail to beat Bayer Leverkusen in the other group game, Chelsea would go through.
"We can get in a very, very good position if we can win our game - of course waiting to see what happens in Valencia-Leverkusen," said Chelsea coach Andre Villas-Boas, whose team thrashed Genk 5-0 two weeks ago.
In Group H, top two AC Milan and Barcelona will look to maintain their winning momentum ahead of the November 23 meeting between the sides at San Siro that is likely to decide who tops the group.
AC Milan visit BATE Borisov on Tuesday, with Barcelona - for whom Lionel Messi netted a hat-trick in a 5-0 thrashing of Real Mallorca on Saturday - away at Czech champions Viktoria Plzen.
With just three points separating surprise leaders APOEL Nicosia and fourth-placed Shakhtar Donetsk, Group G is the tighest in the competition.
APOEL host Europa League champions Porto, with Shakhtar travelling to Russian Premier League leaders Zenit Saint Petersburg.