The first announcement made by new coach Darren Lehmann was to reinstate Watson to his favourite position opening the batting, and declare the 32-year-old was there to stay for the series.
But just three Tests in and the all-rounder could make way for David Warner at the top and push down to No.4, to better balance out Australia's ratio of left and right-handers in playing England off-spinner Graeme Swann.
A more permanent change was foreshadowed in the second innings at Old Trafford when Warner opened the batting as Australia sought quick runs.
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Watson averages 24 for the series without a Test 50, but despite opening being statistically his best position, he says he has no choice but to accept he might have missed his chance.
"As I always say I certainly do love opening the batting in all forms of the game," he said.
"But I do understand the thought process behind it ... about getting some right-handers in the middle of the order because the right-handers have it a bit easier playing Graeme Swann.
"I also haven't scored the runs as an opener in these three Test matches to be able to continue to feel like I'm doing a competent job at the top of the order.
"I'm happy to fit in and contribute wherever I can to stay in."
The frustrating thing for Watson is he's made starts in every innings he's played and was out three consecutive times lbw.
Between the second and third Tests he worked hard at improving his head position and reducing his stride down the wicket.
"I've been working hard on one thing in particular where the ball is seaming back to try and give myself the best chance of being able to get through a ball like that. But even (at Old Trafford), things just aren't working at the moment," he said.
"It's been really disappointing. It's probably been the first time in my career that I feel like I'm actually batting well, but I'm not getting the results that I know I can get."
At Lord's, Watson opened the batting and bowling for Australia for the first time in his career - a sign that his allround ability is still an asset for the team.
Watson has taken just one wicket for the series, but he's bowled 61 overs for 31 maidens, at an economy rate of 1.86.
It's the most Watson has bowled in a series since 2011 and the fastest he's bowled in some time - even matching Ryan Harris for pace.
England great Geoffrey Boycott predicted Watson would go from an opening batsman who bowls a bit, to an opening bowler who bats a bit in this series.
Watson couldn't disagree.
"To be able to take the new ball in the second innings at Lord's and come on pretty early, my role is probably changing a little bit," he said. "But any way I can try and evolve and try and contribute to the team is the most important thing for me.
"My body bowling-wise feels as good as it has ever been.
"I am confident that I can let myself go."