Nemanja Matic played his first game in Manchester United colours as the club beat Sampdoria 2-1.
Matic joined United in a £40million move from Chelsea earlier in the week, and travelled with the side to Dublin to face the Serie A club.
The midfielder started, but it was Henrikh Mkhitaryan who opened the scoring in the ninth minute.
Denis Praet equalised for Sampdoria just after the hour mark, with United heading for a draw in their final game of pre-season.
They face Real Madrid in the UEFA Super Cup on August 8, before opening their Premier League campaign against West Ham that weekend, but will head into those fixtures with confidence.
Juan Mata restored their lead late on, meaning United have won seven of their pre-season fixtures.