Royal Marines are to patrol the River Thames as security is stepped up to ensure there is no disruption of the Boat Race.
Organisers are anxious to prevent any repeat of last year when the annual race had to be halted after Trenton Oldfield swam into the path of the Oxford and Cambridge university crews, narrowly avoiding being struck by an oar.
Organisers have warned against a repeat of anyone taking to the water for the 159th race, with the Marines set to patrol eight miles of the River Thames in inflatable boats.
Boat Race executive director David Searle said: "We are taking additional measures this year and have reviewed all of our actions last year in detail. The Boat Race course is four and a quarter miles long so we have eight and a half miles of riverbank to manage and monitor.
"What I would say to anybody thinking of disrupting the race is that it's unbelievably dangerous. You risk injuring yourself, the crews and the other people following the race. Nobody wants that to happen. This is just a sporting event."
Oldfield, 36, was released from prison in December having served seven weeks of a six-month sentence after being found guilty of causing a public nuisance.
He has since been contacted by the Metropolitan Police by letter and on Twitter to establish whether he was planning any action this year, saying they were "keen to facilitate any peaceful protest".
In a statement, the police stressed they were not offering to organise a protest but to afford him the opportunity to exercise his "lawful rights without causing disruption or danger to themselves or others".
However, Oldfield told The Spectator he would "probably have a ramble across the Cotswolds instead".
Oxford have emerged as clear favourites to win the race after more than 70% of bets were placed on the Dark Blues, according to bookmaker William Hill.