Hard to speculate about its future value. With a card like this, it could be at its peak now, or it could jump if he starts hitting the cover off the ball.
If you're looking to make a profit, I guess there are two ways of looking at it: either sell it now so that you definitely wind up in the black, or hold on, hope for the best, and say that even if it does drop, you didn't invest too much in the first place anyway. Probably depends on your overall way of looking at things.
Then again, I collect for fun, not money, so I might not be the best person to offer advice here...