While Andre Onana has conceded seven goals so far this season, the Cameroonian has been exceptional in goal for Manchester United and has been a clear upgrade on former shot-stopper David de Gea.
However, the 27-year-old, who arrived at Old Trafford following a spectacular season with Inter Milan, will be unavailable for the Red Devils for up to seven games later in the campaign, thus handing Ten Hag a huge blow.
The reason is simple: the former Ajax shot-stopper will report for international duty at the beginning of 2024 to represent Cameroon at the upcoming Africa Cup of Nations. This was unforeseen as Onana had retired from the national team before moving to England.
The goalkeeper had a falling out with Indomitable Lions manager Rigobert Song at the 2022 FIFA World Cup and was sent home before their tournament even ended. Andre later took to social media, announcing his retirement from international football.
However, a U-turn has taken place. The aforementioned pair look to have settled their differences, with Onana coming out of retirement and returning to the national team. The Manchester United goalkeeper started in Cameroon's most recent fixture, a 3-0 win over Burundi that secured qualification for next year's African Cup of Nations.
The competition takes place between January 13 and February 11, and with Onana set to start in goal, he could miss seven games if the Indomitable Lions go all the way to the final.
This means he could be unavailable for Manchester United's Premier League games against Tottenham, Wolves, West Ham and Aston Villa. Additionally, he could miss both legs of the Carabao Cup semifinals and the FA Cup fourth round should the Red Devils make it that far in both tournaments.
And that's not all. While the first leg of the UEFA Champions League round of 16 takes place a week after the AFCON final, Onana could miss that game as well if he is given rest.
Sofyan Amrabat, who joined on loan from Fiorentina, and Amad Diallo are also likely to depart to represent Morocco and Ivory Coast, respectively. Amrabat's inevitable departure is another concern as that will leave Ten Hag short on midfielders.
Regardless, while these are all concerns, the Dutch tactician is currently focused on the weekend, with his team returning to action on Saturday in a tricky clash with Brighton and Hove Albion live on Peacock. The Red Devils aim to return to winning ways after losing 3-1 at Arsenal just before the international break. However, beating De Zerbi's tricky side won't be easy. Click here for more worldwide broadcast listings.