Madden NFL 18
40 Achievements
1,000
15-20h
Trust Your Arm
Lead your team to a win in the Longshot 7 on 7 Game.
10
23.76%
How to unlock the Trust Your Arm achievement in Madden NFL 18 - Definitive Guide
It's 7 on 7 rules and the first to 21 wins. When I did it, I made most of my throws. On defense as Free Safety I didn't really do anything since the opposing QB missed every throw.
Then the last play is a steer the ball QTE. Aim left to avoid the defense then steer right to get it to the WR for the win.
MISSABLE
To unlock this trophy, you must beat the Longshot team in a 7 on 7 game during Act 2. The first team to score 21 points wins. These games are fairly simple. Offense should be easy, just throw the ball to after they make their breaks in their routes. I believe it is impossible to throw an interception in this game. One many occasions I threw the ball right to a defender and they dropped it.
Defense is the most difficult part. When in man coverage stay close to your man by holding which gives you computer assistance. Just don't get beat deep. While in zone coverage jump any routes in the middle of the field. If you somehow lose the game, quit and restart. You may have to re-watch some cutscenes. See here for a video Guide: LINK