WATCH LaLiga LIVE on beIN SPORTS | Sign up to take advantage of our 7-day FREE TRIAL here | AU | NZ

Barcelona had plenty of motivation after Madrid's shock 2-1 loss at Mallorca earlier in the day, but it was the hosts who took the lead six minutes before the break through Giuliano Simeone.

The visitors responded with a Marcus Rashford goal three minutes later and Atletico had Nico Gonzalez sent off on the stroke of half-time.

Lewandowski was in the right place to net a fortunate rebound three minutes from time.

The first half brought plenty of chances at both ends, with Atletico's all-time leading scorer Antoine Griezmann at the heart of the home side's attacking threat.

Griezmann created the first opportunity himself, weaving through the Barcelona defence, but sent his effort straight at keeper Joan Garcia and later fired wide after Alex Baena sent a low ball across the area.

Barcelona's Lamine Yamal nutmegged Gonzalez before playing a perfect pass forward for Fermin Lopez, who put his shot wide under pressure from Nahuel Molina.

Yamal also had an attempted lob from a tight angle hit the upright.

The opening goal came when Simeone timed his run to perfection and controlled Clement Lenglet's long pass before sending his shot from just inside the area beyond Garcia into the corner of the net.

Barcelona was back on level terms after Rashford played a one-two with Dani Olmo and his strike went through the legs of keeper Juan Musso, before Gonzalez saw red for his foul on Yamal on the edge of the area.

Barcelona appeared to have lost its numerical advantage less than one minute into the second half when Gerard Martin was shown a red card for a foul on Thiago Almada, but the referee changed the punishment to yellow after a video assistant referee (VAR) check.

Yamal sent a shot wide after dribbling his way past four Atletico players and Musso made a point-blank save from Ferran Torres as the visitors piled on the pressure.

Barcelona sprung Lewandowski from the bench with 11 minutes left and after Musso blocked Joao Cancelo's shot, the ball cannoned off the substitute's chest and into the net for a lucky but what could prove to be all-important winning goal.

"We all know what happened this afternoon," Barcelona defender Eric Garcia said of Real Madrid's defeat.

"We knew that if we won today, we'd take a very important step forward."

"They dropped back after the sending off, and they're a very difficult team to score against when they sit deep," Garcia added of Madrid's city rival Atletico.

"Some will say they came out to gift us the match, but we had to suffer through it."

With eight games remaining in the league for both Barcelona and nearest rival Real Madrid, the Catalan side is in pole position for a second successive title.

Atletico remains fourth in the standings on 57 points, 19 points off Barcelona, and the sides will meet again at Camp Nou on Thursday (AEST) in the first leg of their UEFA Champions League quarter-final clash.