Argentina team doctor Donato Villani predicts Barcelona forward Lionel Messi will not require surgery and could be back sooner rather than later. The club originally announced that the 28-year-old would miss seven-to-eight weeks after suffering an injury to the internal collateral ligament of his left knee on Saturday against UD Las Palmas.

"I have known Leo for years and I have no doubt that he is going to be ready to play again in the shortest time possible, maybe before the date that was estimated,” Villani said to Argentina outlet Ole. "The injury was to the ligament on the inner part of the knee, a ligament that is extra-articular, that obviously suffers injury like any other ligament, but this one is outside the joint. He avoided a valgus force injury of the joint, it is not a tear that needs surgery.

"This ligament injury takes about six to eight weeks to heal. After that time, the player can be ready to return with no further problems."

Messi’s injury comes at a critical time in the campaign. Barcelona have Neymar and Luis Suarez to hold down the attack until his return, and the absence of Messi could help give much-needed to experience to young players like Munir El Haddadi and Sandro Ramirez. But Luis Enrique’s side will be stretched without their superstar forward.

In La Liga, Messi seems certain to at least miss the October dates with Sevilla, Rayo Vallecano, Eibar and Getafe. While Eibar are off to a strong start, Barcelona are not expected to face serious tests from other Spanish opponents. The challenge might be whether Messi can be effective in November when Barcelona's schedule becomes more daunting.

Barcelona currently sit one point back of first-place upstart Villarreal, with rival Real Madrid behind by a single point. The Catalans will host Villarreal on Nov. 8, and then travel to the Santiago Bernabeu for a test with Real Madrid on Nov. 22. Whether Messi will be back at full fitness will be a topic of much discussion in the coming weeks.

In a rather weak Champions League group, Barcelona seek their first win after a road draw against Roma on Sept. 16. On Tuesday, they host Bayer Leverkusen who are currently in fifth place in the Bundesliga. That key fixture will be followed by two dates with Belarusian club FC BATE Borisov, an opponent that Barcelona should be heavily favored against, so Enrique may consider playing it safe and resting Messi for the home date on Nov. 4.

As for international duty, Messi may be in danger of missing at least two or three World Cup qualifiers. Argentina host Ecuador on Oct.9, and take on Paraguay in Asuncion on Oct. 13. But the big date is Nov. 13, when Argentina host chief rival Brazil, and another demanding match takes place four days later when Argentina face Colombia on the road. If Villani's projections are correct, Messi will be available for those two matches.

While Argentina appear to be a lock to reach World Cup 2018 with CONMEBOL owning potentially five spots, head coach Gerardo Martino may need his top scorer in fine form to earn early wins. Messi has scored 49 goals in 105 caps for La Albiceleste.

Messi has been in typical form this season. Through 16 matches between Barcelona and international duty, the former Ballon d’Or winner has netted 10 goals with five assists.