LONDON -- Royal Marines will be stationed in inflatable boats on the River Thames on Sunday in a bid to prevent the annual Boat Race between English universities Oxford and Cambridge being disrupted by another protester in the water.

Last year's race in southwest London was brought to a halt when a man protesting against elitism and inequality jumped into the water and narrowly avoided being struck by the oars of both crews.

Trenton Oldfield served seven weeks in jail for causing a public nuisance.

"We are taking additional measures this year and have reviewed all of our actions last year in detail," Boat Race executive director David Searle said Friday ahead of the 159th edition of the event. "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.

"There will be an increased presence both on and off the water, including support from the Royal Marines, but as with any security plan I cannot disclose the exact details."

An estimated 250,000 spectators typically line the river bank from Putney to Mortlake for one of England's oldest and most prestigious sporting events.

"What I would say to anybody thinking of disrupting the race is that it's unbelievably dangerous," Searle said. "You risk injuring yourself, the crews and the other people following the race. Nobody wants that to happen. This is just a sporting event."

London police have contacted Oldfield to establish whether he was planning any further action this year, saying they were "keen to facilitate any peaceful protest".

But Oldfield has been quoted as saying he won't be anywhere near the race.

"In spite of the Metropolitan Police's kind offer I'll probably have a ramble across the Cotswolds instead," Oldfield wrote in The Spectator magazine.

Oxford, which lost last year's race by more than four lengths, will outweigh their opponents by just over 21 kilograms (46 pounds) on Sunday.

The Oxford crew weighed in earlier this month at a total of 757.6 kilos (1,670 pounds), while Cambridge came in at 736.4 kilos (1,623 pounds).

The heaviest crew member will be Oxford's Malcolm Howard, a Canadian double Olympic medallist who weighed 109.2 kilos (241 pounds). He's also the oldest crew member at 29.

Cambridge leads the series with 81 victories to Oxford's 76, with one dead heat in 1877.