The Imbuko-Giant pair were the highest-placed South African team, finishing fifth overall. Cannondale Factory Racing’s Manuel Fumic and Henrique Avancini won the race.
The race started disastrously for Carstens and Joubert, who was involved in a crash on the newly introduced 29km first stage.
Joubert crashed in the first 300m when a rider “took him out”, Carstens said.
As a result they finished the stage in 17th place. But Carstens indicated that it was their subsequent ability to minimise their errors and maximise their strengths that led to them overcoming some stiff local competition.
“After the crash we were just trying to get back into our rhythm. We just kept calm,” Carstens told In the Bunch today.
“During stage two we realised we could actually compete against the top guys.
“It was the same in stage three. We were up there racing among the favourites.”
Deon Steyn, the UCI-appointed president of the commissaire panel, later announced the results would stand after he was unable to “find any faults with the route markings”.
“We were coming sixth, but because of that we ended up coming fourth,” Carstens said.
“We were fifth [on the general classification] so we just tried to limit our time losses and we managed to secure our position,” he said, despite a nervy puncture on the final stage.
“There were some big challenges to overcome but I think we handled it very smoothly.
“We rode super well together on the last stage.”
They finished ninth in stage four, behind SA teams NAD Pro’s Matt Beers and Nico Bell and Buys and Beukes. But they managed to do enough not to lose a spot on the GC.
It was Joubert’s first appearance at the Tankwa and Carstens’s first in an all-man team.
The two only linked up this season in their new team set-up, managed by Max Sullivan.
“We had the best support team around us and Marco and I worked very well together. I couldn’t have asked for a better racing partner,” Carstens said.
“We complemented each other quite well. He’s very calm while I’m more out there.
“I’m very good on the climbs where he’s always able to follow me. We’re both really good on the technical sections and I think that was the biggest plus.”
Both Carstens and Joubert are set to take part in the Herald Cycle Tour MTB race in Addo this weekend. It is an individual race near Joubert’s home town of Port Elizabeth.