Boasson Hagen, who triumphed in 2009 and 2015, clocked 19:33 on the 16km Essex course to finish 16th on the stage, 30 seconds down on Boom.
After picking up 12 bonus seconds for a brace of second place finishes earlier in the week, he now lies eighth overall, 19 seconds off Boom.
"I felt quite good actually. I obviously didn't go fast enough to win but the feeling was pretty good. I don't think I did much wrong out there, I can't think of anything I could have done a lot better. I just didn't go fast enough for the win," Boasson Hagen told Cyclingnews.
While the top 10 is packed full of time trial specialists, Boasson Hagen is perhaps the biggest threat to Boom, given his sprinting form. There are three stages remaining, two of which look certain to culminate in bunch sprints, and all of which carry bonus seconds of 10, 6, and 4 seconds for the top three.
"My chances are getting smaller," said Boasson Hagen. "19 seconds, it's hard to get. If you win two stages you have it. But there are three stages left and it's not easy to win stages here with the sprinters that are here. It's going to be a hard one, but we'll try."
One nagging regret will surely be the 10 seconds that went out of the window on stage 2 when he crossed the line first but was later relegated for an irregular sprint.
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"It's true, but I can't… well, I can look back, but I can't change anything. It happened, I can't go back and do it again," he said.
"I wasn't doing it on purpose but I know I went from one side to the other and that's not the right way, so that's what happened, there's no reason to do it but when you look down when you're sprinting, I didn't really see where I was going. It's not any excuse for doing it but I can't change anything anyway. I know I went from one side to another."
While two more bunch kicks are predicted in what has been a sprint-heavy Tour of Britain, there's an air of unpredictability about Saturday's penultimate stage into Cheltenham. The 185km route packs in 2370m of climbing, the major flashpoint being a second-category climb that tops out just 9km from the line.
"I need to have a closer look at the course for stage 7, but we'll make a plan tonight," said Boasson Hagen.
"The time trial doesn't really change a lot. I will just try to go for a win again, and see if we can make something out of it. The team's done really well bringing me to the front, riding on the front, so we just need to keep doing what we're doing, and try again."
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Patrick is an NCTJ-trained journalist, and former deputy editor of Cyclingnews, who has seven years’ experience covering professional cycling. He has a modern languages degree from Durham University and has been able to put it to some use in what is a multi-lingual sport, with a particular focus on French and Spanish-speaking riders. Away from cycling, Patrick spends most of his time playing or watching other forms of sport - football, tennis, trail running, darts, to name a few, but he draws the line at rugby.
