Lionel Messi returned to full training with Barcelona on Wednesday as he nears a comeback from a calf injury.
The 32-year-old missed the whole of Barca's pre-season programme and was not part of their squad for the 1-0 loss to Athletic Bilbao on the opening day of the Liga season.
Messi – whose last competitive outing was for Argentina in the Copa America third-place play-off victory over Chile, a match in which he was controversially sent off – has been doing solo exercises to build up his fitness and sat out the Liga champions' first training session on Wednesday but was pictured with the rest of his team-mates later in the day.
Barca head coach Ernesto Valverde may now consider the Argentina international for selection against Real Betis on Sunday, with Ousmane Dembele and Luis Suarez already ruled out.
Dembele will miss the next five weeks with a hamstring injury and Suarez is out for an indefinite period after injuring his right calf in the shock defeat to Athletic.
Goal confirmed on Tuesday that Messi was ready to rejoin Valverde's squad after enduring a stunted pre-season period due to the Copa America and subsequent injury.
Messi is expected to be named in the matchday squad to take on Betis, and it is likely he will feature from the bench.
A double session has been scheduled for the diminutive frontman during the week, taking his tally to five training sessions ahead of Sunday's clash.
If he is cleared to play against Betis, it will mark his first appearance alongside new signing Antoine Griezmann, who will lead the line in the absence of Dembele and Suarez on Sunday.
The Frenchman played the entire 90 minutes but was unable to open his account for the Catalans as they were frustrated by Athletic, a result that means they start the campaign three points behind rivals Real Madrid, who dispatched Celta 3-1.