Coached by Des Hasler and co-captained by Jamie Lyon and Jason King, they competed in the National Rugby League (NRL) 2011 Telstra Premiership, and finished the regular season in second place (out of 16 teams).

The Sea Eagles then qualified for the NRL grand final, in which they defeated the New Zealand Warriors, claiming the club's eighth first-grade premiership.

Manly lost four first-team players at the end of the season: first-choice halfback Trent Hodkinson, forwards Chris Bailey and Josh Perry, and utility back Ben Farrar.

[2] Manly's season would also see the emergence of key youngsters such as Queensland born halfback Daly Cherry-Evans, who would win the NRL's Dally M Rookie of the Year award, the continued rise of New Zealand born five-eighth Kieran Foran,[3] and winger Will Hopoate, son of Manly's 1996 premiership-winner John Hopoate, who would debut for New South Wales in the 2011 State of Origin series.

Daly Cherry-Evans made his first-grade debut as Manly's starting halfback, but was penalised for a "foot fault" when kicking a line dropout.

[5] The following week, Manly played the grand finalists from the previous season, the Sydney Roosters, without co-captains Jamie Lyon and Jason King, and Glenn Stewart and Steve Matai.

Despite the losses of key players, the Sea Eagles scored their first win of the season, 27–16, thanks to performances from Cherry-Evans and his halves partner Kieran Foran that the ABC described as "outstanding".

An aggressive physical performance from the Sea Eagles saw the Knights reduced to just 13 fit players by the second half, enough to put a full team on the field but with an empty substitutes bench.

[7] April started badly for the Sea Eagles, losing 32–30 to the South Sydney Rabbitohs,[8] and suspending two players—long-serving club veteran Anthony Watmough and squad player Terence Seu Seu—after they were arrested by police and fined for public urination.

[14] Manly started the month of May with a home win over the lowly Canberra Raiders in which Brett Stewart scored his 99th, 100th and 101st tries for the Sea Eagles.

[24] Manly responded to the defeat to the Tigers with another winning streak, beating the Sydney Roosters, the Parramatta Eels and the Canterbury Bulldogs in successive weeks.

Gallop decided to attend the Friday night match, in front of a packed Brookvale Oval crowd of 20,059, leaving Manly to consider hiring security guards to protect him.

A number of players joined the brawl, including Manly's Glenn Stewart and Melbourne's Adam Blair, who the referee decided to send to the sin bin.

A series of Manly and Melbourne players ran from the field and the sideline benches to join the fight, giving rise to a large brawl in front of Brookvale Oval's main stand.

[34] Manly's opponents for the grand final, held at Stadium Australia on 2 October, were the New Zealand Warriors, who had finished sixth on the NRL ladder.

Glenn Stewart returned from his "Battle of Brookvale" suspension, while 2008 premiership winners Jason King and David Williams were the only players missing through injury.

Reflecting what the Irish Times observed from abroad was a long-standing "inherent hatred" for Manly, many Australians supported the foreign Warriors to win the match.

Manly stretched its lead to 16 points after half-time following a try to Glenn Stewart, set up by a blind flick pass from William Hopoate as he was pushed out of play.

[41] In the Golden Boot Awards decided by Rugby League World, Lyon and Anthony Watmough were named in the international team of the season.

Speculation about Hasler's future had been building in the weeks leading up to the grand final, but he appeared to quash the rumours by announcing after the match that he would be at Manly for 2012, the last year of his contract.

[47] In early November, the Manly board suspended Hasler from his duties, alleging that he had been trying to entice fellow Manly staff to defect to the Bulldogs, which the board considered amounted to "serious breaches" of Hasler's employment contract (rumours also surfaced that he had tried to entice players Kieran Foran, Brett Stewart and Tony Williams to join him at Belmore).

[52] After reaching an agreement to commence as the Bulldogs' head coach from 2012, a year earlier than first agreed, Hasler dropped his threat of legal action against Manly.