The suspect, 28, handed himself in at an east London Police station on Friday, the Met said.
He arrested on suspicion of violent disorder and was bailed until mid-August.
Images of three men still wanted over Tuesday's attack were released by the force.
Bottles and other objects were thrown at the coach as it got stuck in traffic en route to the stadium.
The disorder left four policemen injured and West Ham said it would ban for life any fan found responsible.
Two men, aged 18 and 47, who were arrested for pitch incursion have been bailed to return on a date in late May.
A 20-year-old man who was arrested for throwing bottles at police officers has been bailed to return on a date in August.

The Torquay United goalkeeper has yet to make his debut for the National League side, but no-one else at the club can claim to have faced the kind of players the Gibraltar international has.
In the eight caps he has won for the fledgling football nation, Robba has come up against world champions Germany, Euro 2016 winners Portugal as well as Scotland and the Republic of Ireland.
"It's hard to get my head around it. How the hell am I playing against the European champions? It doesn't make sense," he tells BBC Sport.
But since Gibraltar's acceptance as an international footballing nation in 2013, Robba and his team-mates, who had previously relied on the Island Games to give them 'international' matches against the likes of Jersey, the Isle of Man and Shetland, now find themselves on the same stage as World Cup golden boot winner Thomas Muller.
"The whole team pinches themselves while we're there, because most of them are semi-pros at most," says Robba.
"We've got a few professionals, but even the professionals think 'what are we doing playing against the European champions?'"
But from the heights of having four put past him by Portugal in Porto and 'narrowly' losing 4-1 to Greece in midweek, Robba will come back down to earth with a bump on Saturday as he returns to the bench for Torquay United when they host York City in the National League.
It is the 24-year-old's first professional deal and he is understudy to the club's United States goalkeeper Brendan Moore.
But Robba hopes that playing full-time will help ensure that he is the one who gets the nod for the Rock's big matches.
"It's my first year that I've tried to be a professional, so I have to adapt and I'm still adapting and still trying to get used to it," he says of the switch from part-time to full-time football.
"I'm hoping that this can cement my number one place in the long term in the Gibraltar squad and the line-up.
"It's between me and Jordan Perez, who played against Greece, who's a good goalkeeper himself and played well against Greece.
"I've come to Torquay to try and do my best. Brendan's a really good keeper and a really good guy - I try and push him and he tries and push me. That's football, that's what you do.
"Good competition makes us all better and it's the manager's choice who plays."
How long Robba has to wait to make his debut in England is unclear, but his manager at Torquay, Kevin Nicholson, says he has potential.
"Jamie's come in done great for us, trained well and he's keen to show what he can do," Nicholson said.
"Brendan's been doing very well, so he'll keep his spot, but I know that Jamie won't give up."
A man has been arrested in connection with an attack on Manchester United's team bus outside West Ham's Boleyn Ground.
[NEXT_CONCEPT]
In the space of 10 days one footballer will go from taking on the European champions to warming the bench in the fifth tier of English football - welcome to the world of Jamie Robba.