Three no-trumps would have been laydown but you can do nothing about that now. With only nine top tricks and no hope of another trick coming from the minors, you somehow have to make an extra spade. Can you achieve this? Well you need a bit of luck certainly but, even so, it is important to understand the correct way to play the suit. Suppose you win the club, draw trumps and lead a low spade. If West follows with a low card, it might be tempting to play the jack from dummy, but that would only win if West had started with both the king and the queen. A much better bet, after you lead a low spade, is to play the nine, hoping to draw a big card from East. Then, after the defenders cash their two club winners, you will regain the lead and can now lead your remaining spade to the jack. If West started with the ten and at least one of the missing king or queen, this line will give you a second spade trick. (Yes, a smart West might play the king the first time you lead the suit, trying to convince you that he holds the queen as well)