British Cycling performance director Dave Brailsford has refused to reveal his selection strategy for the men's sprint at the 2012 Olympics.
The spot will go to either Olympic champion Sir Chris Hoy or Jason Kenny, who won silver at the 2008 Games in Beijing.
"Selecting that team is very difficult," said Brailsford.
Chris Hoy's major titles
- Olympic gold medals: Four
(Athens 2004 time trial, Beijing 2008 sprint, team sprint and keirin)
- World gold medals: 11
- World medals of any colour: 25
"It doesn't matter what you've done in the past. Our job is to pick the fastest guy."
Kenny, 24, beat the 36-year-old Hoy in the semi-final at the Track World Championships in Melbourne, but the Scot,
who won gold in a dramatic keirin on Sunday
with Kenny in third, has won three of the five sprint meetings between the pair since September.
Regulations permit only one entry per nation per event at the London Games.
The decision does not need to be made until 1200 BST on 3 August, the day before the competition begins, but Hoy would prefer to know sooner if he is to be denied the opportunity to defend one of his Olympic titles.
Team GB hits heights at Track Worlds
Brailsford explained: "The dilemma is that if you select now the riders know what they are doing and can train a little bit more specifically. The downside is that in 16 weeks anyone's form might not be the same.
"That is the conundrum - late for form, but early for clarity of purpose."
Britain won five golds in the Olympic events in Melbourne - half of those on offer - and Brailsford believes his team are on course for a successful performance in August.
"We've got more to come," he added, describing the haul of seven out of 10 Olympic titles on offer in Beijing in 2008 as a "quirk".
"There's no reason why we can't step up again, but then again everybody else is going to improve.
"Form's going to decide what happens at the Olympics now."