* Mourinho's side secure second victory in five days
* Another boost for Real ahead of trip to Man United (Adds details, results)
By Iain Rogers
MADRID, March 2 (Reuters) - Real Madrid are bristling with confidence for the Champions League clash at Manchester United after inflicting a second defeat on Barcelona in five days thanks to a late Sergio Ramos goal in a 2-1 win on Saturday.
Lionel Messi equalled Alfredo Di Stefano's record of 18 'Clasico' goals with an 18th-minute La Liga leveller after Karim Benzema's opener for hosts Real in the sixth minute.
But that was scant comfort for league leaders Barca, dumped out of the King's Cup by their arch-rivals 4-2 on aggregate on Tuesday.
Third-placed Real's victory does little to affect the title race, leaving them 13 points behind Barca with 12 matches left, although it represents another big psychological boost ahead of Tuesday's last-16, second leg at Premier League leaders United.
Real's trip to Old Trafford - last month's first leg at the Bernabeu finished 1-1 - is the club's overwhelming priority and coach Jose Mourinho left key players including top scorer Cristiano Ronaldo and midfielders Xabi Alonso, Sami Khedira and Mesut Ozil out of his starting lineup on Saturday.
It was a strangely low-key affair for a clash between the Spanish giants - the 225th meeting between the sides - and both teams appeared content to settle for a 1-1 draw until Ramos leapt to head home a Luka Modric corner in the 82nd minute.
The Barca players were furious when their penalty appeals for an apparent Ramos foul on Adriano were waved away in the dying seconds and goalkeeper Victor Valdes was shown a yellow card and then a red moments later for furiously berating the referee after the whistle.
It was perhaps a sign of the pressure Barca are under after they followed up a 2-0 defeat at AC Milan last month, which left them on the verge of Champions League elimination, with two defeats to Mourinho's side.
"Winning the league was more impossible when we were 16 points behind but as long as it's not mathematically ruled out Madrid has the obligation to keep fighting," Ramos told Canal Plus television.
"After two consecutive 'Clasico' victories we are going to Manchester convinced we can get through but without being disrespectful to United."
Stuttering Barca were looking for revenge after Real ended their treble hopes on Tuesday but fell behind when Benzema was left unmarked at the far post and clipped an Alvaro Morata cross into the net.
Messi equalised when he got the better of Ramos and sent a low shot past Diego Lopez for his 50th goal of the season in all competitions.
The Argentine has now scored in a record 16th straight La Liga appearance, taking his tally to 39 for the season, and also netted his 18th goal in his 25th appearance against Real, equalling former Madrid great Di Stefano's record set in the 1950s and 60s.
Ronaldo came off the bench with half an hour left and the in-form Portuguese stung Valdes's hands with a powerful free kick before Morata was denied by the Barca keeper in a one on one after he was played through by Pepe.
After Ramos nodded the home side in front, Ronaldo curled another free kick against the post, narrowly failing to score an 11th goal in his last 11 'Clasicos'.
Although they are 12 points clear of second-placed Atletico Madrid, who visit fourth-placed Malaga on Sunday, the defeat was another bitter blow for Barca who had not lost at the Bernabeu in the league in the last four seasons.
Barca have 68 points from 26 matches, with Atletico on 56 and Real on 55 points, 13 ahead of Malaga.
Valencia, who seek to overturn a 2-1 deficit when they travel to Paris St Germain in the Champions League on Wednesday, missed a chance to climb above the Andalusian side when they conceded a late goal in a 2-2 draw at home to city rivals Levante.
Roberto Soldado smashed in a blistering volley moments before halftime to put the home side 2-1 ahead at the Mestalla but a slip by Valencia defender Jeremy Mathieu allowed Jose Javier Barkero to level in the 89th minute.
Despite their erratic league campaign, Mourinho and his players appear to have the upper hand over Barca, a significant turnaround from the Portuguese coach's early days in Spain when their great rivals were almost unbeatable under Pep Guardiola.
The Catalans have won only one of the last eight 'Clasicos' and have not tasted victory in five, their worst run since 2006-08 when Dutchman Frank Rijkaard was in charge.
Mourinho's record against Barca as Real coach is now five wins, six draws and six defeats. He did not speak after Saturday's game, sending out assistant Aitor Karanka instead.
"We didn't play a bad match and I think a draw would have been a fair result," said Barca defender Gerard Pique.
"We felt it was a clear penalty but we can't use the referee's decisions as an excuse and we have to do enough to win games without relying on that.
"It's worrying because Barca is a club that always has to win but I have a lot of confidence in this team and I am sure we will get through it."
Struggling Athletic Bilbao pulled away from the relegation places, climbing to 14th on 29 points after Markel Susaeta volleyed a 63rd-minute goal to earn a 1-0 victory at Pamplona-based Osasuna.
Bottom club Deportivo La Coruna, who appear doomed to the drop, held on for a 0-0 draw at home to Rayo Vallecano despite having defender Carlos Marchena sent off four minutes from time. (Additional reporting by Emma Pinedo in Madrid, editing by John Mehaffey and Tony Jimenez)