Hurdle, a polling analyst who was campaign manager for National at the 2020 election, is credited with masterminding Brown's almost 60,000 vote majority over the Labour-endorsed candidate Efeso Collins.
Lean, a former strategy and governance director at Tauranga City Council, brings invaluable public sector expertise to the table, as well as policy and analytical skills.
Former Beehive staffer Ben Thomas, who joined Brown's team midway through the campaign, has gone back to his job in Wellington with the political PR Agency Capital.
In the interim, a council communications officer, Isabel Gailer, will be the interim media contact in the mayor's office until a permanent team is recruited.
There is believed to be about six policy staff in the mayoral office who were appointed by former Mayor Phil Goff on permanent council contracts.
These staff were not political appointments and it will be up to Brown as to whether or not he keeps them on.
If not, they may be offered redeployment if a suitable job exists in the council group or they may choose to end their employment with the council.
Goff had two political roles on fixed-term contracts that ended with the mayoral term finishing - Chief of Staff and a senior policy and political adviser.