Neymar cancelled out a stunning opening goal by Diego Ribas to ensure it ended all square between Barcelona and Atletico Madrid at the Nou Camp and it's all to play for in the Champions League quarter-final second leg next week at the Calderon. Brazilian forward Ribas came on to replace Atletico's talisman Diego Costa after half an hour and unleashed an unstoppable drive from 30 yards to put the visitors ahead 11 minutes into the second half. But compatriot Neymar finished off a fine pass by Andres Iniesta to level the score 15 minutes later and set up the fourth successive draw in the meetings between the two teams this season as the match finished tied at 1-1. Atletico had successfully cancelled out Barcelona until Ribas' goal, but were clinging on by the end, relying on goalkeeper Thibaut Courtois to make outstanding saves after Neymar's equaliser, denying Iniesta and then Lionel Messi. And Diego Simeone's side's desperation was underlined by the fact six of their players picked up yellow cards over the 90 minutes, while just two Barca players received cautions.