Hernandez scores against MLS All Stars
After a lengthy pre-match fireworks display, Macheda struck after just 24 seconds, collecting an embarrassingly bad pass from MLS defender Kevin Alston and slotting home.
The Italian then headed in a corner from Nani in the 12th minute as United took firm control of the game, watched by a crowd of 70,728.
Local Houston Dynamo forward Brian Ching pulled one back for MLS but that merely prompted a late surge from United with Darron Gibson curling in a beautiful free-kick, before Tom Cleverly coolly finished to make it 4-1.
Hernandez, who joined United from Chivas, was given a warm welcome by many Mexican-Americans in the crowd. He ran on to a long ball and confidently lobbed MLS keeper Nick Rimando.
Canadian Dwayne De Rosario notched a consolation goal in the final moments for the All Stars.