He has been described as the "rock star" of university fundraising with an almost unparalleled record of bringing in the big gifts that vice-chancellors dream about, yet Jon Dellandrea has parted company with the University of Oxford amid rumours of tensions over strategy.
His sudden departure, which will see him leave his post as pro vice-chancellor for development and external affairs this autumn, has prompted a flurry of speculation within the sector, and a warning that Oxford has lost a star man just weeks after announcing a £1.25 billion fundraising campaign.
Dr Dellandrea's departure also coincides with the university's launch of a new centrally managed investment fund, Oxford University Asset Management.
The fund marks a change in the way the university and its colleges handle current endowments of more than £3 billion. Dr Dellandrea was recruited by John Hood, Oxford's vice-chancellor, in 2005 having proved his credentials heading a successful £500 million fundraising campaign at the University of Toronto.
As head of Oxford's 80-strong development office, he led the university's campaign to raise £1.25 billion since it was launched in May.
However, rumours have been circulating about tensions over fundraising strategy between Dr Dellandrea and a major donor, Michael Moritz, who recently gave £25 million to his old college, Christ Church.
Mr Moritz, a California-based venture capitalist, demonstrated the sway donors can have over Oxford affairs when he insisted that his old college move £100 million from its endowment into the OUAM when he handed over his cheque in June. There has been no comment on Dr Dellandrea's departure from Mr Moritz or Dr Dellandrea, and Oxford issued a short statement saying simply that he was leaving "to take up international consultancies".
A senior figure in university fundraising said Dr Dellandrea was a "guru" within university fundraising circles, and suggested that Oxford might struggle to appoint a replacement of the same calibre.
"The sector's buzzing about this. If the rumours are true about outside influence, then I think Oxford would have a difficult time re- recruiting to that post. Jon is one of the best fundraisers in the world bar none, he is amazing. He's a likeable guy and he's very good at his job, he has a demonstrated track record and has done some very good things at Oxford.
"I think he has closed four £25 million gifts this year, that is unheard of - the guy is a total rock star, so you have to think there must be more to it than some disagreement with a donor.
"If not then, wow, Oxford has been really foolish."