Bringing the Heat
Earn a save by throwing all fastballs (one and two-out saves don't qualify; only earned if playing an uninterrupted 9-inning game against the CPU, without switching sides or fast forwarding).
This is simple. Get into a save situation and bring a closer into the game no later than the start of the 9th inning. Throw nothing but fastballs. You will need to be winning by no more than 3 runs to start the 9th inning. If you are up by a lot of runs, you can bring in a pitcher to start the 7th inning and only throw fastballs until the end of the game and you will get a save, and this trophy, no matter the score.

If playing against your weak hitting opponent using your edited roster, with the following slider adjustments adjusted to zero, you'll get this easy:

CPU Contact
CPU Power
CPU Timing
CPU Solid Hits

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