The 28-year-old said this week he had thrown everything into his preparations for the one-day, three-stage event since his return to racing about four months ago.
“I feel good and strong after training every morning. I’ve also done a bit of racing and made progress with every race. This is my first big goal for the year,” he said.
Girdlestone will line up alongside Alex Worsdale, Alwyn Steenkamp and Travis Barrett in the OfficeGuru Racing team.
Their strategy for the Jock Classic included a conservative approach, he said, adding that experience and power in the legs could determine the outcome.
“Our main sprinter, Ryan Harris, is doing a stint in Spain, so we can’t rely on him for stage wins in sprints.”
He would like to try winning it overall for the team, but they would have to play it “very smart”, Girdlestone said.
The strategy could be similar to 2013 when he won it as a member of the Westvaal-BMC team.
Their approach then was to sit back for the first two stages, which covered 48.5km from Nelspruit to White River followed by a 45km ride to Sabie, via Spitskop.
“We watched what was happening, I conserved energy and made sure we didn’t miss any moves,” he said.
“This time I’ll look at the second stage up Spitskop to maybe do something there; possibly get a small move going and just narrow the field down for the final stage [62km from Sabie to Nelspruit].”
If the plan worked, he would “hit it hard” on Long Tom Pass, “go along from midway up and try to hold it to the finish”.
Alternatively, he could give it his all on the last few hills or on the last hill coming into the Mbombela Stadium.
“It’s a long day; certainly a race of attrition. Whoever is the freshest at the end wins the Jock.”
Girdlestone said he would stick to his plan, go on gut feeling and experience, and “not make any silly moves”.
“I’ll make sure not to waste energy and give it all towards the end, where it really counts. I’ll need a bit of luck, but I’m sure with the help of my teammates we can pull off a win.”
Girdlestone, who has always been classified as a climber and general classification rider, said the best way to maintain momentum through the three stages would be to concentrate on recovery between each one.
“You don’t have a lot of time – up to two and a half hours perhaps – and you want to get out of your kit and into compression garments. You want to take in just enough food and hydration.
“Then you want to prepare for the next stage, get ready and get your new kit on. Basically [you have to] hit the reset button so that it feels you’re starting a new race; a new day.”
The Jock has always been one of Girdlestone’s favourite events and he believes it is one of the hardest one-day races in South Africa.
“I enjoy it because it’s always organised well. It has history and it’s good to see who is where in terms of form. There’s also not much hiding in it because of the tough terrain and the route.”
Winning on Saturday would do wonders for his motivation, he said, adding that his goal was to compete in Europe.
“My dream is still to race in the Tour de France one day. I suppose it’s dream big or go home.”