Alexis Sanchez reacts after Arsenal conceded the lone and decisive goal against AS Monaco. (Source: AP)

AS Monaco gave Arsenal a lesson in patient, counter-attacking football to win their Champions League last 16 first leg-match 3-1 in London on Wednesday and take a stranglehold on the tie.

French midfielder Geoffrey Kondogbia put the visitors ahead after 38 minutes when he crashed in a long range shot that took a deflection off Arsenal defender Per Mertesacker, leaving goalkeeper David Ospina helpless.

Bulgarian veteran Dimitar Berbatov, continually jeered by the home fans because of his links with their arch-rivals Tottenham Hotspur, added the second after 53 minutes after a devastating Monaco counter-attack.

Arsenal pulled one back when Alex Oxlade-Chamberlain curled home from the edge of the area, but Monaco restored their two-goal advantage through Yannick Ferreira-Carrasco, who netted deep into stoppage time.

Arsenal wasted several chances with Olivier Giroud spurning four scoring opportunities to leave Arsenal with a mountain to climb in the second leg in Monaco on March 17.

Arsene Wenger’s current team flew out of the blocks against his old one, testing the resilience of Monaco’s rock-solid defence with a series of early raids.

Giroud went close with a header during Arsenal’s opening dominant spell, and then wasted three chances after the break before being substituted, but Monaco weathered the early storm, subduing both the crowd and the home players.

The visitors gradually played their way into the match with winger Anthony Martial and Joao Moutinho looking particularly dangerous, but it was still a surprise when they took the lead through Kondogbia’s long-range effort.

There was no real surprise, however, when they doubled their advantage as they were playing the better football when Berbatov’s powerful finish ended a swift break.

The hosts were given a lifeline in the first minute of stoppage time when Oxlade-Chamberlain pounced on a clearing header before curling home, but their celebrations were short-lived as Ferreira-Carrasco finished emphatically.

Dominant Leverkusen upset the odds against Atletico

Bayer Leverkusen stunned last season’s runners-up Atletico Madrid 1-0 in their Champions League round of 16 first leg on Wednesday courtesy of a fine strike by Hakan Calhanoglu.

The Turkey international scored the 57th-minute winner to set Leverkusen, who are struggling for form in the Bundesliga, on the way to their first ever win at this stage of the competition.

“This was a very, very good game from us,” goalkeeper Bernd Leno, who twice rescued his team in the first half, told reporters.

“We showed a reaction to the criticism of the past week. We had some bad games but tonight we bounced back.”

For Atletico, who were left with 10 men when Tiago was sent off following a second booking in the 76th minute, it was only their second loss in a Champions League away game since September 2013.

The Spanish champions will also be missing key defender Diego Godin for the return leg after the Uruguayan was booked and will be suspended in Madrid.

“They play as they do and they do it well,” said Atletico coach Diego Simeone.

“We each had a clear chance and they took theirs and we didn’t. It could have been a worse result. But I am confident for the return leg.”

Leverkusen had hoped the European stage would lift their game after a rocky start to the year sent them down to sixth in the Bundesliga.

They did not have to wait long for a chance with Atletico striker Mario Mandzukic clearing an Emir Spahic effort on the line in the 12th minute.

The Bosnian defender came even closer in the 26th when his thundering drive bounced off the crossbar.

The Spaniards needed almost 40 minutes to find their feet and responded with a chance of their own, Leno clearing a cross at the last moment with Antoine Griezman ready to head in.

Leno saved the hosts with a brilliant reflex effort on the stroke of halftime, palming away a powerful volley from Tiago.

In a very physical encounter in which coaches Simeone and Roger Schmidt had a heated argument on the sidelines, Leverkusen grabbed a deserved lead through Calhanoglu.

Karim Bellarabi drew three players on to him before cleverly flicking the ball on for Calhanoglu who lashed the ball into the roof of the net.

Atletico, who will be without Godin and Tiago in the return leg, were toothless even when Simeone brought on striker Fernando Torres to form a three-pronged attack for much of the second half.