Twelve months ago, Foster was an automatic selection for Steve Redgrave's coxless four crew, but a debilitating back injury, which left him struggling to walk, changed all that.
Now, after four months out of the sport, he faces a battle with Ed Coode for a place alongside Redgrave, as the great Olympian bids for a record- breaking fifth gold medal in Sydney.
After winning his place in the crew, Foster's road to Sydney has been far from smooth. With an appearance that lends more to surfing than rowing, Foster initially struggled in the shadow of his illustrious crew-mate.
He missed several races after putting his arm through a glass window, but quickly regained his place in the boat. With the Olympic Games in his sights, he was devastated when doctors recommended surgery on a long- term back injury.
Now, instead of joining Matthew Pinsent and James Cracknell in Redgrave's "Oarsome Foursome", he will take his place in the British international eight for Henley's Grand Challenge Cup.
But with selection for the World Championships in Canada made soon after the 150-year-old regatta draws to a close, Coode and Foster know eagle- eyed selectors will be watching every stroke.
"We decided that changing the composition of the coxless four would not be wise at this stage of the season," the British team manager, David Tanner, said.
"Tim is on his way back to full fitness and has been working hard in recent weeks. However, the crews will remain the same for Henley and the World Cup in Lucerne the following week.
"Tim raced in the eight at the recent World Cup regatta and finished second. He's a loyal team player and he understands our decision."
Redgrave's crew are regarded as the clear favourites to secure their senior member his 18th Henley title in the Stewards' Challenge Cup.
The "Oarsome Foursome" face Johnny Searle's Molesey Boat Club in Saturday's semi-finals, a race the world champions are expected to win easily.
That should set up an intriguing battle with the powerhouse Danish national team, who are smarting for revenge following last year's narrow Henley defeat.