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Alcaraz was replaced as the world No.1 by Jannik Sinner after defeat in Monaco, but he responded here with a controlled 6-4 6-2 win in one hour and 25 minutes.

During a tense opening set, Alcaraz was put through his paces by Virtanen, who squandered four break points across the third and fifth games of the opening set.

He was made to pay for those missed opportunities when Alcaraz got the better of his serve in the final game, with the Spaniard taking the lead at the second attempt.

From there, the No.1 seed assumed control, breaking Virtanen early in the second set, only for his Finnish opponent to return the favour and get back to within one game.

However, Alcaraz hit back with a love service game against the serve and sealed his progression in the same manner, teeing up a date with Tomas Machac in the next round.

"It feels great to be back and to get another win in front of my people in Barcelona, it means everything," Alcaraz said.

"This morning was my first practice here to adapt to the conditions. Different conditions to Monte-Carlo but overall I am really happy with the way that I played."

Elsewhere in Barcelona, there was no trouble for No.2 seed Lorenzo Musetti, who also progressed from his opening-round ties.

Musetti emerged with a 7-5 6-2 victory over home hopeful Martin Landaluce, which was his first victory since the Australian Open last 16 against Taylor Fritz.

The Italian will take on Corentin Moutet for a place in the quarter-finals.