After an injury-hit last season, their squad was once again hampered in their outing against Arsenal as both Rasmus Hojlund and new signing Leny Yoro were forced off, leaving both out of this one.
The Red Devils will also remain without several key players who are yet to join the squad following their involvement in either the 2024 European Championships or Copa America, with Bruno Fernandes, Diogo Dalot, Alejandro Garnacho, Lisandro Martinez, Luke Shaw, Kobbie Mainoo, Altay Bayindir, Facundo Pellistri all still on holiday.
Man United fans will also have to wait to see Joshua Zirkzee's first appearance in Man United colours as the striker did not make the trip to America due to his involvement with the Netherlands at Euro 2024, and Zirkzee is not set to join up with the squad until they return to Carrington.
Victor Lindelof and Aaron Wan-Bissaka may not feature against Betis as both are heavily speculated to depart from the club in the coming weeks, leaving Ten Hag's options even slimmer in the defensive area.
Toby Collyer has caught the eye in the middle of the park for Man Utd in their three pre-season fixtures so far, and the 20-year-old is likely to start alongside Casemiro again in this one.
The absence of Hojlund due to injury could see Ten Hag opt to shift Marcus Rashford into the striker position with Jadon Sancho coming into an attacking quartet alongside Mason Mount and Amad Diallo.
Manchester United possible starting lineup:
Onana; Ogunneye, Evans, Maguire, Amass; Casemiro, Collyer; Amad, Mount, Sancho, Rashford