Although a clean sweep of trophies is off the table following the FA Cup defeat at Wigan Athletic, Guardiola has already improved on last season's lack of silverware, with one trophy now secured and the league title sure to follow. Whether or not the Champions League makes it three, City have taken on a dominant air this term, and it showed at the national stadium.
Arsene Wenger sprung a surprise in his selection, opting for a three-man defensive system which had stymied City at Wembley in last season's FA Cup semi-final victory.
But it backfired spectacularly with Arsenal all at sea to allow Sergio Aguero to score for a fifth meeting in a row, the Argentine bringing up 30 goals for the season with a glorious goal assisted by the much-maligned Claudio Bravo.
City stalwarts Vincent Kompany and David Silva also netted in the second half as Guardiola's men went through the gears and the Gunners had no response.
Wenger has now lost all three of his finals in this competition and the disquiet over the Frenchman's reign in north London is sure to return.
The Gunners set out to counter and should have gone ahead when Jack Wilshere charged through the middle before feeding Mesut Ozil in the right channel and the German's excellent centre gave Pierre-Emerick Aubameyang a gilt-edged chance that Kyle Walker's lunge and the legs of Bravo combined to snuff out.
As unexpected as that save was, astonishingly the Chilean's next contribution was to set up the opening goal as City began to dominate.
What looked a rudimentary punt upfield turned into a slide-rule pass as Aguero nudged Shkodran Mustafi out of the way - the German opting to complain to Craig Pawson rather than chase his man - before closing on an advancing David Opsina and sending a delicate lob over the goalkeeper and into the net.
Wenger was soon forced into a change as Sead Kolasinac replaced Nacho Monreal, with the Arsenal response amounting to an Aaron Ramsey free-kick straight at Bravo and a chance for Aubameyang that the covering Kompany extinguished with a minimum of fuss.
Arsenal were once again in Pawson's ear when Fernandinho, having already being booked, clattered Wilshere to no sanction, but the Brazilian pulled a hamstring early in the second half and Bernardo Silva replaced him, with Guardiola tiring of throttling back to protect against the counter.
Bravo was certainly at full pelt as he charged out to close down Aubameyang, and the striker should have done more to punish the goalkeeper's wild air kick than pull him to the ground and concede a free-kick.
But City were soon out of sight, Kompany extending their lead with an instinctive finish before setting off on a limb-flailing celebration as years of injury misery were given a golden full stop.
Six minutes later City were celebrating again as Arsenal began to wilt, Silva turning sharply away from Hector Bellerin and lashing low past the helpless Ospina.
There was no further damage, but the inquest for Wenger will begin on Thursday at the Emirates Stadium, where there will be little time to ponder, as Guardiola and City visit with the intention of restoring their 16-point Premier League lead in mind.
Key Opta stats:
- Manchester City’s 3-0 win over Arsenal is their biggest ever cup final victory, as well as the Gunners biggest ever loss in a cup final.
- Manchester City have won the League Cup for the fifth time in their history – only Liverpool (8) have won it more often.
- Arsenal have lost six of their eight League Cup finals, including each of their last three – the only domestic trophy Arsene Wenger has failed to win with Arsenal.
- In fact, the Gunners are the first side in League Cup history to lose in three successive appearances in the final (2007, 2011 and 2018).
- In contrast, Man City are one of four sides to lift the trophy on four successive League Cup final visits (Aston Villa, Liverpool and Manchester United).
- Pep Guardiola has triumphed in seven of his previous eight major domestic and European finals, losing only to Real Madrid with Barcelona in the 2011 Copa Del Rey final.
- Manchester City kept a clean sheet against Arsenal for the first time in 12 games in all competitions – since a 2-0 win in January 2013.
- Arsenal had just two shots in the whole of the second half, failing to have one on target. In fact, the north London side’s two shots on target came in the opening 23 minutes.
- Sergio Aguero has scored 15 goals in 13 appearances in all competitions in 2018; more than any other player in top five European leagues.