Writing off Arsenal has always been a dangerous business and it was obvious why last night. In winning here with a goal from Thierry Henry, Arsene Wenger's side rose from the bottom of the Group C and back into serious contention for a place in the quarter-finals.
This much-needed victory was built on a sixth consecutive clean sheet, which owed much to three fine saves by David Seaman and also to the determination of a revamped backline and the tireless work of Patrick Vieira.
Arsenal were grateful also for two misses by Lyon after Henry had headed in an Ashley Cole cross to leave them with real grounds for optimism ahead of the return with Lyon next Wednesday.
Wenger was without three key defenders, Martin Keown, Silvinho and Igor Stepanovs, because of injury and ineligibility, and he moved Gilles Grimandi to centre back alongside Tony Adams. The obvious fear was that Sonny Anderson and Steve Marlet might prove too quick and agile.
That danger was soon evident when a long pass from the back caught Grimandi hesitating and left Marlet with a shooting chance from the edge of the area. David Seaman, rushing off his line, did well to get a hand to the ball and deflect it for a corner.
The watching Tord Grip must have been impressed with that, and with Lyon starting in neat, lively fashion it seemed Seaman might be in for a busy night. The French side's use of the flanks and the willingness of Anderson and Vikash Dhorasoo to run at opponents were quickly apparent, and it needed a low save by Seaman to deny Marlet again just after the quarter-hour.
But this was not one-way traffic. Arsenal gradually settled, enjoyed plenty of possession and had the pace to worry Lyon's defence on the counter-attack with Henry back in the starting line-up after injury.
Yet it was Henry's strike partner Nwanwko Kanu, making his first start since New Year's Day, who might have given them the lead when he manufactured for himself a clear chance in the 18th minute.
A dazzling run took the Nigerian past several Lyon defenders but, after drawing the goalkeeper Gregory Coupet, he clipped his shot wide of the far post. His kick at an advertising hoarding told of his frustration.
Although Henry drew a low save out of Coupet shortly after, Lyon twice came close to breaking the deadlock before the interval. Seaman made another sharp stop to deny Dhorasoo and saw another slide wide.
Yet as Lyon's threat dissipated as halftime approached, Kanu produced another fine touch from which Henry went agonisingly close in the 45th minute. After flicking the ball into the Frenchman's path, Kanu saw Henry's shot flashed inches wide.
Arsenal went close again not long into the second half. Kanu, having one of his most impressive games of a season interrupted by injury and affected by poor form, was again a central figure.
This time he caught out Edmilson, a player once coveted by Wenger, and advanced into the area before having a low shot smothered by Coupet.
Though Lyon continued to play with pace and flashes of skill, Arsenal were defending with increasing confidence, Grimandi and Ashley Cole epitomising determination.
Still, though, they needed Seaman to rescue them when Lyon carved out their first clear chance of the half. Marlet's clever pass released Anderson and the 37year-old goalkeeper tipped the Brazilian's shot wide.
The value of that save was highlighted when Henry gave Arsenal the lead two minutes later. Cole burst down the left flank, wriggled past Eric Deflandre and produced a perfect cross for Henry to head in from close range.
"We were a little bit lucky," admitted Arsenal coach Arsene Wenger. "David Seaman kept us in the game against a very good and courageous Lyon side, but we are on a roll at the moment. They were very strong up front and will be a dangerous side to play at Highbury."
LYON: Coupet, Deflandre, Edmilson, Violeau (Malbranque 74 mins), Foe, Laigle (Delmotte 83), Dhorasoo (Govou 74), Muller, Brechet, Anderson, Marlet. Subs Not Used: Hugues, Loko, Chanelet, Linares. Booked: Foe, Muller.
ARSENAL: Seaman, Dixon, Adams, Grimandi, Cole, Lauren, Parlour, Vieira, Kanu (Vivas 90), Pires (Ljungberg 69), Henry. Subs Not Used: Manninger, Wiltord, Malz, Luzhny, Pennant. Booked: Cole, Adams. Goals: Henry 58.
Referee: Urs Meier (Switzerland).
