Manchester, Sept. 11 -- Manchester United marked their return to the UEFA Champions League with an emphatic 4-0 victory over competition debutants Sabah FK, while newcomers Como 1907 announced their arrival on Europe's biggest stage with a convincing 4-1 win over RB Leipzig on an action-packed Matchday 1.

Michael Carrick's Manchester United side took control against Sabah with a dominant display, with Matheus Cunha opening the scoring midway through the first half, according to the UEFA Champions League website.

The visitors had a chance to respond when Joy-Lance Mickels came close to finding an equaliser, but United quickly stamped their authority on the contest with two goals in the space of three minutes before half-time.

Bruno Fern...