* Advantage Atletico after 1-1 draw at the Nou Camp
* Diego stunner cancelled out by Neymar equaliser (Writes through)
By Tim Hanlon
BARCELONA, April 1 (Reuters) - Two special goals lit up the Nou Camp on Tuesday as Barcelona, aiming to reach the Champions League semi-finals for the seventh year in a row, shared a 1-1 draw with Spanish rivals Atletico Madrid.
Brazilian substitute Diego fired an unstoppable bullet of a shot into the top corner of the net from 30 metres to open the scoring for La Liga leaders Atletico in the 56th minute of the quarter-final first leg.
Andres Iniesta then spotted a gap in the visiting defence 15 minutes later and threaded the perfect through ball for Diego's compatriot Neymar to beat goalkeeper Thibaut Courtois with a curling right-foot effort from a tight angle.
"We got a good result but the tie is still open," Atletico coach Diego Simeone told a news conference. "It was all down to enormous work from the team.
"It was a game of different styles and each team fights with the armoury they have. Barca played their usual way with a lot of possession, moving the ball around, one against ones.
"I like to play against Barca because you learn and you improve," said Simeone.
Pinto was brought in as the only change to the Barca side that defeated Manchester City in the previous round, coming in for injured Victor Valdes, and he put them in trouble in the opening minutes.
The keeper's clearance went straight to Arda Turan and he found Villa who fired wide in front of goal.
It got worse for the home side when centre half Gerard Pique went off with a back problem after being injured in a challenge with Costa.
Barca gradually worked their way more and more into the game and an Iniesta strike was blocked by Diego Godin before Costa had to leave the field with what appeared to be a hamstring injury.
Lionel Messi had a header comfortably saved by Courtois and Neymar shot over the bar but Atletico finished the first half stronger and this time Pinto came to the home team's rescue, diving to deny Villa.
Diego's blistering shot from distance sparked Barca into action and their pressure finally paid off with Neymar's spectacular strike.
"As with any player trying to improve their level, the goal will boost Neymar's morale," said Barca coach Gerardo Martino. "He played well as did the team.
"I was happy with the style and the way we played. We didn't get the result we wanted but I think that if we repeated that game with the chances that we had it could be very different."
The second leg at the Calderon is on April 9 and Courtois said the home crowd could be a big help to Atletico.
"We scored a brilliant goal through Diego and then we defended very well," said the Belgium goalkeeper who is on loan from Chelsea.
"A 1-1 draw is a good result and at the Calderon I think anything is possible. With our fans behind us it's like having an extra player and hopefully we can put on a good performance."
Barca captain Xavi believed Atletico were lucky to escape with a draw.
"We deserved to win," said Xavi. "We had more scoring chances but they worked very hard in defence and it was very difficult for us to find a way through." (Editing by Tony Jimenez)