Hansi Flick questioned the value of having VAR following Barcelona's 2-0 Champions League loss to Atletico Madrid, after Marc Pubill avoided being sent off for a bizarre handball incident. 

Goals from Julian Alvarez and Alexander Sorloth saw Atleti leave Camp Nou with a smash-and-grab 2-0 win, with Pau Cubarsi's red card late in the first half costing Barca.

Cubarsi was sent off for a last-man foul on Giuliano Simeone amid a rare foray forward from Atleti, and Alvarez curled the resulting free-kick into the top-right corner.

Sorloth's second goal also came against the run of play as Barca produced a defiant performance with 10 men in the second half, though Flick felt referee Istvan Kovacs and VAR Christian Dingert should have evened things up.

In the second half, Atleti goalkeeper Juan Musso took a short goal-kick to Pubill, who had replaced the injured David Hancko as a first-half substitute and been booked shortly afterwards.

Pubill, appearing to think the goal-kick had not been taken, stopped the ball with his hand and rolled it back to Musso, with the officials allowing the goalkeeper to retake the kick.

Last season, a similar incident saw Aston Villa defender Tyrone Mings concede a penalty for handball in a 1-0 defeat to Club Brugge, and Flick felt Atleti were fortunate. 

Asked by Movistar if he agreed with Cubarsi's red card, Flick said: "Maybe it is, maybe it's not... I'm not sure if he touches him enough because the ball was behind them. 

"But the situation in which Pubill touches it with his hand and the referee doesn't give anything, for me, is very clear. 

"I don't know why the VAR hasn't come in. He's a German referee and he's incredible. 

"We all make mistakes but with this type of situation... Why do we have VAR? It should be a penalty and a second yellow for the player."

Barca's defeat came just four days after they beat Atleti 2-1 in LaLiga, and on that occasion, Diego Simeone was incensed by Gerard Martin having a red card rescinded following a studs-up challenge on Thiago Almada.

Asked about the Pubill incident, Martin said: "The goalkeeper plants the ball down and plays it. The player stops it with his hand. The referee doesn't see it live, but the VAR has to tell him."

Wednesday's victory was Atleti's first at Camp Nou since February 2006 under Pepe Murcia, ending a run of 25 visits to the stadium without winning (D8 L17).

Barcelona, meanwhile, have been eliminated from each of their three previous two-legged knockout ties in the Champions League when losing the first leg at home. 

They have also lost three of their last eight home matches in the knockout phase (W4 D1), after only losing four of their first 45 (W31 D10).

But the Blaugrana came close to wiping out a 4-0 first leg deficit when they faced Atleti in the Copa del Rey semi-finals last month, and Flick will not give up on their chances.

"We believe in ourselves. In the second half, we did very well with one less player," he said.

"They also have quality up front. It wasn't easy to defend them, but we had chances to win this game."