The break stayed away from the peloton for the majority of the 258km race after forming about 15km from the start. Janse van Rensburg was caught with some 28km to go.
He rode among the select group at the front for roughly 215km.
SA was represented by Janse van Rensburg and Nicholas Dlamini after the original four riders – Daryl Impey, Willie Smit, Louis Meintjes and Clint Hendricks – withdrew for fitness or logistical reasons.
Janse van Rensburg was happy to have made a major contribution to the race in national colours.
“The race went really well for me,” Janse van Rensburg told In the Bunch today.
“I had two options in the race – either to save all my energy in the first half to try and finish in a reasonable position, or to try getting into the break and show off my SA jersey.”
Janse van Rensburg initially chose the former option before changing his plans.
“Nicholas [originally] wanted to go in the break, which was good,” he said.
“He tried a lot in the opening kilometres, but there is only so much one rider can do by making it into the break. There were [quite a few] attacks and counter-attacks at the start.
“After about 15km I decided to help Nicholas cover the moves. I then went on to follow the right move and made it into the break of the day.”
He enjoyed the experience of riding in the leading group in what is arguably the most prominent one-day race in the cycling calendar.
“I had an amazing day in the break; it felt good and I enjoyed riding at the front with thousands of spectators next to the road,” Janse van Rensburg said.
“I think I did the best I could for SA. You really have to be honest with yourself and realistic about the result you get.
“There’s no shame admitting that there are better riders than you,” he said, after withdrawing from the race with just under 20km to go.
After being caught in the break, Janse van Rensburg managed to hold on for several kilometres before getting dropped, he recalled.
“I didn’t have anything left to drag myself up the last two climbs, so I decided to withdraw.
“I knew I gave 100 per cent and I have no regrets,” he added.
The elite men took on seven laps of a 24km Olympic circuit following an initial 90km stretch. The entire route featured over 5 000m of climbing.
“The route was very hard once we started the laps,” Janse van Rensburg said. “There was a 6km climb with a six per cent average gradient before a technical descent into the city.
“Then there was another short and steep climb, which was followed by a series of turns before we hit the 6km climb again.”
Janse van Rensburg, who rides for the Dimension Data WorldTour outfit, said he saw an opportunity to represent SA at the world champs after the withdrawal of the initial four riders.
“I asked the federation [Cycling SA] if it was possible for me to take part as we had four spots [to fill].
“We managed to arrange everything only a few days before the race and on Friday I was on my way to Innsbruck.”