"To be honest he had a really hard three-year-old campaign and then we were getting him ready for the Triple Crown at Hastings," Rogerson said.
"He went well the first leg, and we went back down for the second leg. It's a five-and-a-half-hour float trip from where we live down to Hastings and he picked up a bacterial virus in his blood.
"It really knocked him out on his feet, so we tried to get it all back on track again and we thought we did, and he went a couple of good runs, but we still weren't 100% happy.
"So, we turned him out, gave him a good spell and everything was clear when he came back in."
Sharp 'N' Smart has had two runs back, finishing well back over 1200m first-up in August before running an improved second at Te Rapa on September 15.
That performance and a subsequent piece of work at Te Rapa convinced Team Rogerson the stayer was back in order.
"He had a good exhibition gallop at Te Rapa on Friday," Rogerson said.
"Ryan Elliott rode him, and he usually rides the horse. He trotted back up the straight then worked over a nice 1400 metres. Ryan said it was the best he's ever worked on his own, and he said he just felt enormous.
"That was really encouraging."
Plans where Sharp 'N' Smart heads will be finalised after the gelding runs on Saturday.
Sharp 'N' Smart needs a top three finish to qualify for the Caulfield Cup (2400m) on October 19.
"If he happens to run in the first three, we've got the Caulfield Cup option," Rogerson said.
"He's nominated for the Cox Plate, and we've got other races leading into the Melbourne Cup, so we'll just work everything out after Saturday.
"He's travelled over really well. He got off the float here yesterday morning about 6.30, got off bright, very bouncy, had an easy day and he looks super.
"It's a very good field, and he's drawn not too well again, but if he's hitting the line hard in that last 200 metres, I'd be very happy."
