Updated

Barcelona says Lionel Messi will be sidelined for up to three weeks after re-aggravating his right hamstring strain, an injury that has hampered his ability to play over the past six weeks.

The club says tests performed Tuesday revealed the muscle strain.

Messi first injured his hamstring on April 2 in the first leg of the Champions League quarterfinals against Paris Saint-Germain, and re-aggravated the injury in Sunday's 2-1 win at Atletico Madrid.

Messi was making his first league start since the injury but left the field in the 68th minute after Barcelona had made all three substitutions and was trailing 1-0. The team rallied without him.