Boyd explains Grayson substitution after Saints are beaten by Bristol

Grayson had been performing impressively and was largely accurate from the tee, propelling his team into a 21-14 lead by the time he was replaced.

Harry Mallinder came on and soon missed a penalty that he would normally expect to make, leaving the gap at seven points.

And Bristol pounced late on, scoring in the 75th and 77th minute to secure a dramatic success at Franklin's Gardens.

Boyd was asked why Grayson was taken off, considering the fly-half had controlled the game well.

And the Saints boss said: "We were just looking for a slightly longer kicking game.

"Harry's got a bigger boot and we thought that if we could get a slightly longer kicking game and pin them back, the scoreboard pressure would mount and they'd have to make some changes to the way they were playing.

"But as it turned out, it didn't happen that way.

"It may well have been a mistake and we'll reflect on that. It's my call.

"We were 21-14 up with five minutes to go and I thought we were in with a shout, but in the blink of an eye it was 28-21.

"It was massively disappointing but I guess that's why they're top and we're fifth.

"We controlled the kick-off and lost it and they scored so the last five minutes cost us after clawing our way back into the game."

Saints had been 14-0 down but had a huge chance to win the game after mounting an impressive comeback.

And Boyd added: "We gave them two platforms and they scored two tries in the first half but we scored a try just before half-time and played particularly well for 30 minutes in the second half.

"We gave them an opportunity through a mistake deep in the half and we know that's how they can attack - and they did."