Who will fill Nicholas Serota's shoes at Tate?

Sir Nicholas Serota has overseen Tate's growth into an international art megabrand

There is one sentence in the press release announcing Nicholas Serota's departure from Tate that stands out.

It is a direct quote from the man himself and reads: "I leave an institution that has the potential to reach broad audiences across the UK and abroad, through its own programmes, partnerships and online."

It's that word "potential" that sticks out. What does he mean "potential"?

He's talking about an institution that has developed - on his watch - from a well respected but modestly visited gallery in Pimlico to an international art megabrand boasting the most visited museum of modern art in the world (Tate Modern), two hugely popular regional galleries, a country-wide network of partnerships and a lending programme that sees Tate's collection of British art presented in major museums from Beijing to Boston.

By most people's reckoning, Nicholas Serota has already delivered on Tate's "potential".

But clearly, he doesn't see it that way, which is the measure of the man and an insight into why he has made such a success of his time at Tate. He doesn't do complacency.

His comment about "potential" reflects three aspects to his character: a predisposition not to blow his own trumpet, a relentless drive, and a challenging nature.

He doesn't want the next incumbent to think he or she has an easy ride: there is work to be done. He might be leaving, but he's setting the agenda before he goes.

And who might that person be to come in and realise Tate's "potential"?

Maria Balshaw has built her reputation at the Whitworth and Manchester Art Gallery

The front-runner I reckon is Maria Balshaw, who has done a splendid job as the boss of the Whitworth in Manchester, a role she's coupled with being leader of the city's cultural programme.

Then there's Iwona Blazwick, the long-serving director of the Whitechapel Gallery in east London, who helped shape Tate Modern's curatorial philosophy when she was working for the gallery in the late '90s. She has long been tipped as Serota's successor, and the path from Whitechapel to Tate is the one he took.

Of the internal candidates, the most obvious is Frances Morris, but she has only just taken on the job as director of Tate Modern. The recently departed Jessica Morgan could also be a contender, but again, she has barely settled into her role as the boss at the DIA Art Foundation.

The search team is bound to look further afield. Klaus Biesenbach from MoMA PS1 might get a call, as could super-curator Carolyn Christov-Bakargiev, and quite possibly Michael Govan of the LA County Museum.

Finally, Tim Marlow from the Royal Academy and Matthew Slotover, the co-founder of Frieze, are both notable figures who could bring something new to the party.