They also need to be strong and good enough on the ball to hold off several defenders.
The main weakness of a 4-3-3 is that the single centre-forward can be left isolated, and is naturally underloaded whether playing against two or three centre-backs. This means you need a player in this position who is willing to do lots of work that may bring little or no reward. They also need to be strong and good enough on the ball to hold off several defenders.