Messi was one of eight Inter Miami players away on international duty, but Gerardo "Tata" Martino's team showed their strength in depth as they extended their unbeaten run in all competitions to 12 games.
With Miami battling to rise from its pre-Messi position at the bottom of the Eastern Conference into the top nine, they know they have little room for error but their night began poorly. Campana went close to a hat-trick after the break with a deft touch goalwards from a low Jordi Alba cross but Melia got down well to save.
But with 12 minutes remaining, Sporting pulled a goal back with Alan Pulido's 13th MLS goal of the season, the Mexican pounding on a loose ball and then beating Callender with a clinical finish. Claudio Bravo then made it 2-0 in the 53rd minute with the Argentine full-back starting off a swift exchange of passes before bursting into the box and providing the finish.