Football Manager 2021 Xbox Edition

There is a quick and easy way to get this achievement.

Start a new game, and go to challenges. From here you want to use the injury crisis challenge.

In this, you start with 8 of the first team out with long term injuries, which is a massive help. Check the youth/reserve teams for any more injured players. If you do have any, promote them to the first team. If you don't, don't worry. Just skip through a few days at a time, and use 'instant result' on every game.

It seems like this challenge makes your players more injury prone. So keep an eye out on the inbox for news of any player getting injured. If you get any that aren't in the first team, just promote them as mentioned earlier. For me, after playing just 2 games I had 14 players injured across my first and reserve teams.

I just then promoted them all to my first team, saved before the next game, and used instant result to simulate the match. If you fail to win simply load the save back up and re simulate it until you do.

Once it's done you'll get the achievement.

I found the injury crisis method needing a bit of luck/RNG on who is injured. Easier if we can guarantee injuries, which we can.

From the home screen, select New Game > Career.

Add the top 4 divisions of England > Start game > Create Manager and Appearance > and select Man City. Go through the menus until you have the game ready.

Go to Squad > Filter > tick reserve players. Promote Jayden Braaf and Philippe Sandler to the first team (click on player, actions, promote to the senior squad).

You should have 7 injuries in Squad > Medical Centre > Injuries (in the bottom left):
1. Philippe Sandler for 4-6 months
2. Benjamin Mendy for 3 months
3. Kevin De Bruyne for 3 months
4. Aymeric Laporte for 3 months
5. Gabriel Jesus for 3 months
6. Olexander Zinchenko for 2-3 months
7. Jayden Braaf for 7 weeks - 3 months

We are one month away from the first competitive game in the Premier Divison. Who you play is randomised and we need three more injuries.

Either use the search bar for the names below or go to the Sky Bet League Two (in England) and sign the following players - just suggest terms and pay what they want in both transfer fees and wages:
8. Top Lapisle from Colchester United
9. Thomas McGill from Crawley (might be in the Reserves)
10. Tristan Francois-Vernal from Leyton Orient (again, check the Reserves)

Check McGill and Francois-Vernal are not in your reserves and promote them if needed. Both went straight to my first team.

Continue and Instant Result all friendlies until all 3 have signed. Check you have 10 players in Squad > Medical Centre. I ended up with 13 players injured but only 11 were going to be injured long enough for the first league game. Go on holiday until the first match. Check you have 10 in the senior squad injured, as players can recover at different rates in different save games, particularly Francois-Vernal who is 17, quicker to recover.

Save your game. Quick Pick the team and Instant Result. If you lose, reload and try again.

It is possible for transfers to fall through due to injuries causing them medical to fail, usually if they have more than 3 months injured.
Feel free to lost other options in the comments below and I'll list them as alternatives.

Other options include:
?

Pretty easy.

Start the challenge ‘Injury Crisis’ and set it on hard difficulty. Select the French League and play as PSG. When you start off most of your team will be out injured. Promote youth players to fill your match day squad and save before the first game (I think mine was against Reims at home). Autoselect the starting lineup and click instant result.

I got this first try. Good luck!