De Arrascaeta turned out for his country in a friendly loss to Japan on Tuesday before embarking on the 25-hour flight to Sao Paulo to represent his club side and his second-half cameo proved key.
Robinho opened the scoring for the Belo Horizonte-based side, drilling home through a crowd after Hernan Barcos saw his low effort bounce back into play off the post.
However, VAR handed Corinthians a route back into the game, with Thiago Neves being adjudged to have tripped Ralf. Jadson kept his cool to convert from the spot, but it was De Arrascaeta stole the limelight late on.
He converted a flowing counter-attack with just nine minutes to go by dinking the ball over the onrushing Cassio to secure his side the victory.
The win gives Cruzeiro their sixth Copa do Brasil triumph, with no team having recorded more, whilst they also become the first side to win the trophy twice in succession.