Read this article and answer this question The Eagles traveled to western Pennsylvania to take on longtime in-state rival Steelers at Heinz Field.  After a scoreless first quarter, the Steelers were able to get on the board first with Rashard Mendenhall's 13-yard touchdown run for a 7-0 lead followed by Shaun Suisham's 20-yard field goal for a 10-0 lead at halftime.  The Eagles went to work in the 3rd quarter as Michael Vick found LeSean McCoy on a 15-yard touchdown pass to shorten the lead to 10-7.  The Steelers increased their lead with Suisham kicking a 37-yard field goal to make the score 13-7.  The Eaglesl took the lead with Vick hooking up with Brent Celek on a 2-yard touchdown pass for a 14-13 score.  However, the Steelers were able to drive down the field and Suisham wrapped up the game with a game-winning 34-yard field goal for a final score of 16-14.
How many points did LeSean McCoy's 15-yard touchdown pass shorten the lead of the Steelers to?
3