Double up the jab, follow him back if you can, cause he is off balance if he is leaning back.
If his lead arm worries you as your heading in, then try to position yourself to use your lead glove to cover his elbow point as you go in and launch a shot from there as you move.

Not many people do it, but if your outreached by a lengthy lead arm that follows you around and keeps you at a distance you can lightly move that arm on the way in.Chances are his reaction will be to push the opposite way to what you try to lightly move it so you slip around the same way that you pushed cause he will then help you by reacting the reverse.

(I'm the alternate styled one in here) I try and come up with different stuff then the usual...have fun with it or ignore me if you feel the urge ;-).