However, manager Gus MacPherson must have been raging in the fifth minute when slack defending allowed Tom Brighton to get in a shot which was brilliantly saved by teenage keeper Chris Smith.
St Mirren finally began to take an interest in the game, and although striker John Sutton was being closely marked, Charlie Adam managed to find some space but wasted a couple of half chances.
Home forward Stewart Kean was having a quiet afternoon with only a weak header to show for his efforts when he suddenly came to life in the 28th minute. After being tripped by Craig McKeown, he sent keeper Paul Jarvie the wrong way from the penalty spot.
Simon Lappin might have extended the lead barely four minutes later, but after opting not to go for goal himself, his attempted pass was a poor one.
Eddie Malone went close for Clyde towards the end of the first half, but the second period belonged to St Mirren, and Sutton snuffed out Clyde's challenge 20 minutes from full time with a firm header from point-blank range.