JOHN Jackson continued to maintain hopes of Great Britain's first Olympic bobsleigh medal since 1998 as he topped the standings on the second day of official training on Thursday.

Jackson, who lives with British women’s number one Paula Walker in Paxcroft Mead, finished 0.02 seconds behind Russia’s two-man gold medallist Alexander Zubkov in the first heat of the day and improved to pip Zubkov by 0.01secs in the second.

Jackson had placed seventh and third on the opening day of official training on Wednesday.

Although a number of four-man teams use official training runs to test runners and lines, and some – including American pilot Steven Holcomb – often do not push, Jackson's times raise genuine hopes that he will be in the hunt for a medal when competition gets under way on Saturday.

Jackson admits he is still battling his fitness – but insists it’s no pain, no gain in his pursuit of glory.

Jackson defied medics to compete this season after a ruptured Achilles last summer, which required pioneering surgery never before attempted on an elite athlete.

He is looking to upgrade his fifth place at last year’s World Championships in Sochi, where he clearly likes the track, finishing fifth again at last year’s test event.

“I wouldn’t say I am fully fit, I am progressing still day by day by day,” said Jackson, who also claimed a first career World Cup podium with a silver last December and is competing at his second Games.

“I am in the best shape I can be but I would love to be running three or four tenths quicker over a sprint. I am now sprinting faster than I was before I did my Achilles, so I can’t complain.

“We are coming into the Olympics as the best prepared team that we can be. There is pain sometimes, even just walking around, it hurts walking up and down hills, it still hurts when I get to the bottom of the bobsleigh track.

“It is part of the life of being an elite athlete. We have just got to get on with it, it doesn’t hurt when I am pushing so that is the main thing.”

Jackson admits he thinks about the twists and turns of the Sanki Sliding Centre in his sleep and will have had 40 practice runs down the track when he lines up for race day on Saturday.

“I think it is a great track to drive. It suits our equipment, it suits us as a team at the start and we will see what happens in the race,” he added.

“It does pay to be quite mentally strong but in terms of expectations we have had a relatively good season in terms of results. We have done a lot of moving and changing things around some of which has worked, some of which hasn’t.”