On a balmy Wednesday night that saw the Aviva morph into a kind of ersatz Emirates, Arsenal melded the old with the new.
To start with the latter: manager Unai Emery, defensive midfielder Matteo Guendozi, attacker Emile Smith Rowe. The former: the same rickety defence on set-pieces and a reliance on Mesut Ozil.
That they found a late equaliser in a pre-season friendly against Chelsea is not cause to hail a new-found resolve, and the goal's arrival can partly be attributed to the fact that Arsenal have had their new manager and most of their squad together for the last month. Chelsea, with Sarri's arrival delayed and Kante, Hazard, Willian and Courtois all missing, have not had such luxuries.
Having fallen behind in the fifth minute, Arsenal sent the game to penalties with the final kick of the game. Mesut Ozil was played a sharp reverse ball to Reiss Nelson, who's drive parallel to the end line was diverted to the net by Alexandre Lacazette.
They ultimately won 5-4 on penalties: Alex Iwobi converting in sudden death to capitalise on Ruben Loftus Cheek's miss.
Ozil played the full game and was Arsenal's most important player. Ineffective for the first half-hour, once he switched to the left and dropped deep to exploit space behind Cesc Fabregas, Ozil linked up majestically with Aubameyang, Mkhitaryan and later substitutes Iwobi and Lacazette.
During that half-hour, however, the game was Chelsea's. They made an inauspicious start - an emoji in a pre-game Instagram post told the world that it was "time to get warm" in the Ivory Coast - but came to kick-off in furious form. With the front three of Hudson-Odoi, Pedro and Morata pressing intensely, they took the lead in fashion familiar to Arsenal fans.
When defending set-pieces during the latter third of Arsene Wenger's reign the Arsenal defence resembled a rickety structure that could collapse in on itself if it was so much looked at with some intensity, and thus it proved within five minutes of kick-off. Cesc Fabregas was roundly booed as he trotted over to take a corner, applauding in response before whipping a ball that went in off the forehead of the unmarked Antonio Rudiger.
Chelsea continued to dominate from there, and should have been two ahead ten minutes later. Callum Hudson-Odoi, playing wide right of Chelsea's front three, Hector Bellerin before falling under Bellerin's subsequent challenge in the penalty area. Alvaro Morata's penalty was pushed away by Petr Cech. Morata looked just as shorn of confidence as he did for much of last season, and while Pedro and Hudson-Odoi buzzed with intent either side of him, Morata lumbered about scuffing at shots, miscontrolling the ball, and at one point he whacked the ball out of play rather than have to turn and hold the ball up for support.
Among Chelsea's most impressive performers in the opening half was new signing Jorginho, who calmly shuttled about stitching play together. At some points he did Pedro's thinking for him, instructing the winger where to move for a pass yet to be played. With Arsenal's defence happy to dawdle high up the field, Jorginho pinged a series of balls over them, one of which resulted in a half-diverted Hudson-Odoi shot being headed of the line by Mustafi.
Such was Jorginho's influence, even Willy Caballero looked relatively calm stroking the ball to him when Arsenal put him under pressure.
Willy's only notable blunder two minutes before the break: he flapped at a Bellerin cross that narrowly evaded the loitering Aubameyang and fell to Sead Kolasinac, who could only force a corner. By this stage Arsenal had grown into the game thanks largely to the decision to swap Mesut Ozil from the right-wing to the left.
Exploiting space behind Fabregas, Ozil was menacing, but was frequently let down by the support from left-back Kolasinac. If Ozil has a wand for a left foot Kolasinac's is a wildly swinging croquet stick over which no control is exerted. Kolasinac wasted Arsenal's best first-half opening, knocking the ball too far ahead of him in the penalty area after neat link-up play with teenager Emile Smith Rowe.
Smith-Rowe has impressed during pre-season thus far but here he was frustratingly timid, and Arsenal looked much more dangerous once he was replaced by Alex Iwobi. It was Iwobi who should have equalised in the final five minutes for Arsenal, with his six-yard tap-in saved superbly by Willy's splayed replacement, Marcin Bulka.
Prior to that Alex Lacazette blasted wasted a glorious one-on-one chance after a delicious pass by Ozil. Ultimately, he atoned and sent the game to a shoot-out.
Arsenal played a stronger side throughout and made fewer substitutes, eager to steal a march on the World-Cup depleted squads of City and Chelsea in the first weeks of the Premier League season.
Ozil, Mustafi, and Elneny ended by waving to the crowd and parading a banner emblazoned with "Thanks for your support", while Chelsea trooped off without one, neatly summing up the fact that, preparation-wise Arsenal currently have the edge.
The sides meet on August 18th, where it just might tell.