The Spain international midfielder has trained normally with the rest of the Blaugrana squad and could be given a starting-XI place in the match at the BayArena
The Spain international missed Barca's last two games with a knee injury but was included in coach Pep Guardiola's squad for the trip to Leverkusen even though his involvement in the first-leg was in doubt.
Busquets trained normally with the rest of the Barca squad at the BayArena on Monday evening in a clear sign that he could start for the Catalan side in Tuesday's match.
The news comes as an important boost to the defending European champions, as Guardiola has had to deal with an injury crisis at Camp Nou this season.
Andreu Fontas, Ibrahim Afellay and David Villa are long-term absentees for Barca, and that has forced the 41-year-old coach to include five players from the club's B team for the match at Leverkusen, which kicks off at 20.45CET.
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