The 29-year-old, who was in charge of the Middle Road club for the 2013-14 campaign when they finished 14th in Sussex County League Division 1, will take over at the end of the season from caretaker bosses Matt Brace, Mark Hilfiker and Paul Dunk.
Kane Louis started the season as Mussels manager this year but was replaced by Simon Funnell, who left last month which resulted in Brace, Hilfiker and Dunk taking over.
O’Toole resigned as Shoreham boss in 2014 as he wanted to play again, after a lengthy injury absence. However, after brief spells with Haywards Heath and Steyning Town, he says his playing days are now behind him: “I wanted to play again but after three years out with injury, my legs couldn’t do what I wanted anymore but I felt I had too much to offer to just sit and watch games.
“I’m really looking forward to next season and am counting down the days until I get started.
“The job appealed to me again and I know Stuart Slaney, the chairman, as well.
“When I left before, there was the nucleus of a good squad here and they were all young, they just needed game time. We beat Littlehampton, who finished second that season 3-0 and only lost 1-0 to East Preston, who went on to win the title and you can ask anyone who was there that day, we should have won.
“That team just needed to stay together but the players all ended up going to different clubs.”
Mussels will return to pre-season training on June 21 and O’Toole, who will watch games for the remainder of this season, is looking to be challenging at the top.
He said: “Every manager wants the same at the start of a season – to win the league.
“We’ll try to win every game and won’t take anyone lightly. To say we’ll be challenging for the title would be a massive shout. If Eastbourne Town don’t go up, they’ll be looking to win it, there’s Pagham and Newhaven as well, while Haywards Heath will be up there
“It will be a hard task to win it and I’d be lying if I said we weren’t looking to but 19 other managers will be looking to as well.
“The first thing I need to do is sort out a a strong spine of the team. That’s my main focus and signings will then attract more signings.”
Mussels chairman Stuart Slaney said: “This choice of the new appointment was chosen due to the fact that Bryan knows the club, has been here before and has a good network of players. The standard of player the club is expecting is mirrored by Bryan’s plan for next season.
“The club’s goal is to ensure we can compete for the league title and bring in more all local players, plus bring back some players that our previous manager cut loose.
“Everyone at the club is really looking forward to next season and we wish Bryan and his management team all the best for what lays ahead.”
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