The BIGS 2

To perform a Double Steal, you need to have Runners on 1st & 2nd base.

Try and have 2 Fast Runners (4+ Stars - Legendary Running Helps).

Lead-off the base first.

Then when it gives you the option, select "Double Steal" (Right-Bumper). When the pitch is thrown, both runners will attempt to advance. Use turbo if you want to play it safe. The lower the catchers arm rating, and whether they have turbo or not can make or break your double steal. Don't swing the bat. You'll have to risk getting a wheelhouse strike. Both runners need to make it to the base to count as a Double Steal.

If the Catcher has a legendary arm, only attempt this with 5+ or Legendary Runners, and Use Turbo.

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If you're having trouble getting this achievement, try this:

Play as the American League All-Star team. Put Ichiro and put Grady Sizemore in the outfield. Ichiro gets a full bar of Turbo at bat, and Sizemore's special ability is a +1 for Outfielder Running. This makes Sizemore's & Ichiro's running to "Legendary".

Play as the "Away" team so you bat first (You can restart easily if you screw up) and play against a weak team (Like the Washington Nationals).

Put Ichiro first in the batting lineup, and Sizemore second. Get a single with Ichiro, and then a single with Sizemore. Lead off, and select "Double Steal". Use Turbo to increase their running speed. You should hopefully get it, and the achievement with it.