Our model gives the Home win a 46.4% probability, the highest of the three outcomes, so Manchester United are slight favourites at Old Trafford. United have dominated this fixture historically, with five wins in eight meetings and only two defeats, including heavy home wins like 6–2 and 1–0 in previous European ties. Both sides start this Champions League league phase on 0 points, but United’s home record in Europe is usually strong and they will want a fast start in front of their crowd. Roma arrive in decent form with a big 4–0 win in Serie A, yet they have often struggled away to top Premier League sides. With our model leaning 46.4% toward the hosts, 24.2% on the draw and 29.4% on Roma, backing Manchester United to edge a high‑tempo game at Old Trafford fits both the numbers and the history.

Our model gives BTTS Yes a 60.0% probability, making goals at both ends more likely than not. Recent meetings between these clubs have often been open, like the 6–2 at Old Trafford and the 3–2 in Rome, where both teams found the net. United’s attack at home tends to create plenty of chances, but their defence can still leave gaps, especially against sides who counter well like Roma. Roma’s recent results, including a 4–0 league win and a 2–2 away draw in pre‑season, show they can score even when they concede. With 60.0% on Yes versus 40.0% on No, and both teams motivated to make a statement on matchday one, a 2–1 or 2–2 type scoreline feels very plausible and aligns with a United home win plus over 2.5 goals.

Our model gives Over 2.5 goals a 60.9% probability, clearly ahead of the 39.1% chance on the Under. Past clashes between Manchester United and Roma often produced high scores, including 6–2, 3–2 and other multi‑goal thrillers. United’s recent friendlies, like a 2–1 win over Atletico Madrid and a 1–1 draw at PSG, show they are creating but also allowing chances. Roma’s pre‑season and early‑season results, such as a 4–0 home win and a 2–2 away draw, point toward an attacking approach but a defence that can be exposed. With both teams’ strengths tilted toward the final third and this being an opening Champions League fixture where neither side wants a dull start, a 2–1 or 3–1 United win fits our other picks. The model’s 60.9% edge to Over 2.5 and the attacking form of both sides support backing goals here.