The Barcelona boss iterated during the pre-match press conference that Inter Milan will pose a major challenge, considering they will step up after their loss in the reverse fixture at Camp Nou last month.
The striker has not yet been declared fit by Barcelona's medical team but he will travel with the squad to the San Siro.
Messi, who missed Barcelona's 5-1 thrashing of Real Madrid in last Sunday's El Clasico which led to the sacking of Julen Lopetegui, was reportedly set to be absent for three weeks.
Malcom insisted he wanted to make history with Barcelona after scoring his first goal for the club in the 1-1 Champions League draw against Inter. The extra rest should only benefit the Argentina worldwide.
Messi's return means Barcelona are without just three first-team players, with Samuel Umtiti, Thomas Vermaelen and Sergi Samper missing the trip to Milan. Barcelona won their third straight game, beating Rayo Vallecano 3-2 behind a Luis Suarez brace.
Barca were without a win in four league games and defensive errors looked set to play havoc with their title challenge. Over the last three games, Suarez has scored six goals.
Luis Enrique is yet to pick him for Spain but it would be hard to justify ignoring the full-back again when the next squad is announced later this week.
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