New Zealand coach Mike Hesson suggested last week that, with fingers crossed, Guptill might be ready to return for the start of the three-game T20 series against the West Indies, on December 29 in Nelson.
Guptill is reluctant to be more specific other than to say he's hoping to be back "fairly soon".
You can't blame him for being cautious. He's had problems with both legs in recent seasons and is taking it small steps at a time.
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A couple of minor setbacks in the last fortnight have added to the sense of not getting ahead of himself.
"I'm definitely improving day by day, which is a great sign," the Auckland batsman said.
"But I have to give it a little bit of time to make sure it's right, and if I come back too early it could be a month or more out of the season, like it was last year."
Guptill could be forgiven for being frustrated at sitting out the West Indies matches.
After all, his ODI debut in January 2009 produced a memorable 122 against the Windies at Eden Park.
At Westpac Stadium two years ago, Guptill struck the second highest ODI score ever, a stupendous 237 not out to carry New Zealand to an easy World Cup quarter-final victory over the same opponents.
Guptill has been back hitting balls for three weeks and yesterday had a fielding session in Whangarei with the New Zealand team. It felt good and he's had a positive report from the team medical staff.
In 149 ODIs, Guptill is averaging 42.71, with 12 centuries. New Zealand need him back fit and firing.
Guptill admits he hates watching cricket, especially if it's his team he's watching and he knows he should be out there.
"It's been frustrating watching the last few games Auckland have been playing.
"All I want to do is be out there giving my all, whether it's for Auckland or New Zealand."
Guptill and his Auckland team mate Colin Munro formed a promising opening combination in India a few weeks ago. Now Munro will team up with Central Districts lefthander George Worker in what might amount to a contest to be Guptill's partner in the longer term.
Guptill believed Munro showed encouraging signs in India, in which he made a blazing T20 century and a rapid half century in one of the ODIs.
"It's exciting for him," Guptill said of Munro.
"It's a new role and he's had a great start in India. He's got to make sure he pushes on and gets that consistency everyone strives for.
"He's a free spirit when he plays. It's not always going to come off but when it does it's going to be exciting to watch."