The Sunderland striker has been ruled out of pre-season with a thigh injury.
The 33-year-old picked up a thigh injury last month that has ruled him out of the remainder of the club’s pre-season schedule.
He has already missed three games while they have been in France and is likely to be absent for the club against Borussia Dortmund on Friday.
It leaves major doubts over whether he will be fit for the opening game of the season against Manchester City later this month.
Stockdale has moved to reduce any worries though, saying that the results from a scan on the injury have provided positive news.
“I will be perfectly honest, Jermain has been for his scan and we’re all hopeful it’s not as bad as first feared,” he told the club's official website.
“I wouldn’t want to put a date on it but Jermain will be eager to be back fit as soon as possible, and although we won’t take risks with him the news we got was positive.”
It now remains to be seen whether Defoe is fit in time for the start of the new Premier League campaign.
If it turns out that he is not, it is only likely to further increase manager David Moyes’ desire to add another striker to his squad as soon as possible.
Who that could be though remains to be seen, with Sunderland not the only Premier League side in the hunt for a new goal-scorer this summer.