Sergio Aguero was forced off 42 minutes into his first home start for Barcelona and taken to hospital due to difficulty breathing.
The Manchester City legend was visibly struggling towards the end of the first half against Alaves, laying down on the turf after an awkward clash in the penalty area.
Fortunately, Aguero was on his feet four minutes later and was able walk off before ex- Liverpool star Philippe Coutinho took his place at the Nou Camp.
El Chiringuito presenter Jose Alvarez Haya later reported that the 33-year-old's heart rate was much higher than it should have been, although he was 'doing okay' on his way to hospital for checks.
It was the Blaugrana's first game since sacking Ronald Koeman on Wednesday and was played in front of a crowd of just 37,278.
Aguero has been taken to hospital after troubling breathing ( Image:
NurPhoto/PA Images)
The club's B-team coach, Sergi Barjuan, took charge as Memphis Depay broke the deadline shortly after half-time by producing a stunner from 20 yards out.
It took just three minutes for the visitors to equalise as experienced wide man Luis Rioja scored from close range to make it 1-1, the final scoreline.
Barca's finishing was what let them down once again, while Alaves were only able to muster three attempts on goal, a stark contrasts to the La Liga giants' 16.
The results sees manager-less Barcelona ninth in the league table, with club legend Xavi Hernandez the favourite to take over.
Aguero was able to walk off ( Image:
Getty Images)
But the Spaniard's current club, Al Sadd, issued a strong statement on Friday evening, adding that there had been no official approach from the Blaugrana for president Joan Laporta's No.1 choice.
"In response to what's circulating recently, the Al Said management reaffirms that Xavi has a two-year contract with the club and is fully focused on the team's upcoming matches, to maintain our lead at the top of the league and to defend the title."
Media officer Ahmed Al Ansari later confirmed there had been no official offer from Catalonia.
"Any club that has a bit of professionalism is supposed to negotiate with the other side if it wants a player or coach who is under contract."
Xavi himself was coy when asked about the links as he stated in a press conference: "I am focused on my work with Al-Sadd and I cannot talk about anything else.
For now, though, Barjuan is in charge has set out his aim for the short term.
"I want to put some joy back into the team and get them enjoying their football again," the interim boss said.
"I need all the players to be plugged into turning this situation around. It is important for them to be united."
Barjuan added: "The players are the same but the concepts might change.
"The real challenge is for the players and they have shown what they are capable of doing. They need to believe in what we want."