Their fans sang the song of the champions but Chelsea they did not step out at Wembley like the team which destroyed all before them on the way to the Premier League title.
They looked as though minds were elsewhere. It wasn't only the players who allowed their focus drift. They even forgot to pull on their black armbands in the first-half.
Chelsea had not played in a meaningful game for more than a fortnight and suddenly pertinent questions were thrown into the air about what had been going on since that jubilant night at The Hawthorns.
Antonio Conte rested players and his team partied through the chaos of goal-crazy victories against Watford and Sunderland. There were days off to rest, mini-breaks abroad and the surreal sight of the John Terry farewell parade.
It is impossible to criticise Conte after the impact he has made in his first year in English football. Without his decisive intervention last autumn, this season would have been nothing like a success from a Chelsea perspective – and a new deal for the manager remains a crucial first piece of summer business for the club to conclude.
But even before Alexis Sanchez sliced through the blue shield at Wembley, albeit in fortuitous circumstances, and put Arsenal into a fourth-minute lead, something was amiss.
Intensity, after all, is not something to be turned on with the flick of a switch. It is generated through great effort and concentration and then guarded.
Chelsea came into the game like a decorator woken an hour into his sleep, handed a paint-brush and told he'd missed a bit.
Unlike the champions, Arsenal had been locked in competitive action up to the wire on the final day of the Premier League season as a result of meandering hopelessly through the late winter and early spring.
They summoned a flourish which proved inadequate to scramble into the top four but it meant they were on it from the opening phase of the FA Cup final when Chelsea were not.
Arsenal were a fraction sharper to the ball, their touch more certain and their passes were crisper. They even had more bite in the tackle. This is Arsenal. Against Chelsea. All stereotypes were off.
On those rare moments when Chelsea went forward in the first-half, Arsene Wenger's team sprang out with menace as if the players had swapped shirts before the game, not afterwards.
Sanchez working the spaces either side of David Luiz with great effect. Danny Welbeck hit a post and twice Gary Cahill kept his team in the contest with clearances from the goal line.
A more clinical team than Arsenal would have had this won before the break but Chelsea hung in and the increasingly exasperated figure of Conte yelled himself hoarse and cajoled from the touchline.
The Italian's impeccable record as a manager in league football over the years is not matched by his record in the cups but he knew his team did not lack heart.
Twice they fought back to win the semi-final against Tottenham when he made changes to help having started with Diego Costa and Eden Hazard on the bench.
In the final, they both started in the team, but Conte refused to idle.
Chelsea were just about up to speed by the time the interval came and returned for the second half with extra purpose and intent, pressing higher up the pitch.
Growing in confidence, Arsenal defended their lead with their back-three and David Ospina simply refusing to live up to the pre-match billing as the weakness in Arsene Wenger's team.
Conte answered a call from the crowd to send on Cesc Fabregas to exert more control but no sooner was he on than Chelsea were reduced to 10 men, with Victor Moses sent off for a dive.
Such was their desperation to make up lost ground that Moses took a chance when already on a yellow card and was rightly penalised by referee Anthony Taylor.
Briefly, it seemed as it if might be the jolt the champions needed to shock them into action.
Diego Costa levelled but there was no way back from Aaron Ramsey's goal.
Chelsea paid for their sleepy start and will settle for the title and a return to the Champions League after last season's slump.