BARCELONA, Spain -- With Lionel Messi and Luis Suarez in unstoppable form, Barcelona didn't need much help to stay on course for another Spanish league title.
But it got an unexpected boost on Saturday when Diego Costa was sent off for insulting the referee with more than an hour to play in Atletico Madrid's last realistic chance to pressure Barcelona.
Suarez and Messi finally broke down the undermanned Atletico and scored two late goals to earn a 2-0 victory and increase Barcelona's lead over second-placed Atletico to 11 points with seven rounds remaining.
In clearing the path to what would be Barcelona's 26th league title, Messi reached a new personal milestone with a competition record 335th victory, overtaking Iker Casillas on 334 wins.
Costa was sent off in the 28th minute for insulting referee Gil Manzano for not calling a foul after Barcelona's Jordi Alba tackled the striker. Costa rushed in close to Manzano, who responded by whipping out a red card.
A livid Costa was kept in check by his teammates, before rival defender Gerard Pique put his arm around him and guided him off the pitch.
Atletico coach Diego Simeone complained that other players weren't also penalized for using similar language on the field but said he understood the referee's decision on Costa.
"If the referee interpreted that there was an insult, then he was correct in sending him off," Simeone said.
Barcelona, however, had a difficult time making good on its extra man.
Goalkeeper Jan Oblak kept Atletico in the match as long as he could even as Messi started to find holes in Atletico's defense.
Atletico still mustered one late push forward but couldn't break through, including with a header by Rodrigo Hernandez and Alvaro Morata's blocked effort.
Suarez finally beat Oblak with a curling shot from outside the area that went in off the post in the 85th minute. Messi capped the win on the break with a demoralized Atletico trying to answer Suarez's goal.
"We know that that we have taken not one, but two steps (toward the title)," Suarez said.
Messi and Suarez have fueled Barcelona's quest to defend its league title all season long. Messi leads the competition with 33 goals, followed by Suarez with 20. Both also scored late goals on Tuesday to salvage a 4-4 draw at Villarreal.
Manchester United manager Ole Gunnar Solskjaer watched the match in person, before the Spanish club visits Old Trafford on Wednesday for the first leg of their Champions League quarterfinal.
JEERS AT BERNABEU
Karim Benzema saved Real Madrid from another embarrassing slip this season, scoring two headers to beat Eibar 2-1.
Madrid coach Zinedine Zidane criticized the poor play of his team in the first half, when many fans at the Santiago Bernabeu Stadium jeered their sloppy performance.
"We don't like being jeered, but our supporters come to see their team play well," Zidane said. "Our fans know that the season is over. The only thing left is to try and finish in second place (in the league)."
Madrid remained in third place at 13 points adrift of Barcelona.
Rayo Vallecano ended Valencia's run of 17 games without a loss in all competitions after winning 2-0.
Sergi Darder scored two goals from long range, including an 89th-minute winner, to give Espanyol a 2-1 win at regional rival Girona.
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