Ronald Koeman had an eye-catching statement about the importance of Lionel Messi to Barcelona as he was quizzed on both his own future and that of his captain.

Barca can no longer win LaLiga following Sunday's results, with Atletico Madrid and Real Madrid both victorious elsewhere as the Blaugrana lost 2-1 at home to Celta Vigo.

Atleti's triumph meant Barca would not have been able to finish this season as champions regardless of their result against Celta, though Koeman's side could not deliver anyway.

Although they led through Lionel Messi in the first half, Santi Mina netted before the break and then late on to seal a fine victory for the Galicians.

It was a familiar sinking feeling against Celta, who have now beaten Barca five times since the start of the 2014-15 season – tied with Madrid for the most in that time.

However, this campaign has been particularly disappointing at Camp Nou, with a seventh loss the Blaugrana's most in a league season since nine in 2007-08. That was also the last time Barca had fewer than their current 76 points after 37 games (64).

Questions about Koeman's job security are to be expected then, but he responded on Sunday: "I'm not going to answer that."

Of greater concern to Barca fans, though, will be a decision on Messi's next move, with the legendary number 10 out of contract for the second consecutive close-season.

His header against Celta made this the 300th different LaLiga game he has scored in – Madrid great Raul is a distant second on 186 – while he tallied 30 league goals for the ninth time in 12 campaigns.

Since the turn of the year, no player in Europe's 'top five' leagues has been involved in more than Messi's 31 goals (23 goals, eight assists) and Barca are of course keen to keep their captain.

Asked if Messi was appearing at Camp Nou for the last time, Koeman said: "Hopefully not.

"He is still the best in the world and has also shown today that it is impossible to play without him.

"He has scored 30 goals in LaLiga and has given us many points in LaLiga. It's a question for Leo. For my part and the club, let's hope he stays with us.

"Because if Leo's not here, we have a doubt who's going to score the goals."

Left-back Jordi Alba was offered the same question and replied: "Let's hope not, although it's a decision [Messi] has to make."

Alba appeared to excuse Koeman, meanwhile, as he reflected on a tough run-in for Barca, who have won only one of their past five matches.

"We haven't won four games," he said. "It's a shame. We players are to blame. We have to give a good image in Eibar [in the final game], give it our all."

The coach added: "The problem wasn't today. We had the opportunity against Granada [another 2-1 defeat] and today we have lost in a similar way. That's how we feel.

"It has to be accepted because, in the end, the champion will just be the champion. And we won't have done enough."