They say there is no substitute for quality. The problem was that yesterday at the Emirates the quality remained among the substitutes until the 66th minute. Up to then these teams, both of whom are in European competition, were level. It's just that if you had landed in North London from Mars you wouldn't have been able to tell who was in the Champions League and who was in the Europa League.
But then enter, stage front, left and centre, Robin van Persie and the difference became clear. With each game that goes by, the Dutchman's value to Arsenal increases, exponentially, even as his contract, which expires in 2013, winds down. That is because at the moment it is his contribution that keeps the Gunners competitive. His two goals last weekend ensured victory against Sunderland and here against Stoke he was the difference. Back in August, his goal against Udinese in Italy helped put Arsenal in the group stages of the Champions League.
Yet to great surprise he was not part of the starting XI. But Arsène Wenger explained his leading player was feeling the effects of a busy week and could have been left out completely. He said: "I thought Robin looked tired after playing Marseilles on Wednesday. He had a muscular tightness and I was not sure to involve him today on the team sheet. I had him checked and he was medically OK to be on the bench. But you think 15 times about it before you leave him out."
But the effects of leaving Van Persie out were clear. Without him, Arsenal were ordinary and directionless, and lacking authority anywhere on the pitch. Marouane Chamakh was given his first league start of the season and with it he had the chance to shine. Instead the Moroccan's performance only focused the spotlight more intensely on the Dutchman.
Within a minute of being introduced, Van Persie, 28, created a goal-scoring chance out of nothing, putting in a cross that was just too high for Laurent Koscielny. His arrival sent an air of tangible expectation around the Emirates and a frisson of fear in the Stoke defence. Tony Pulis, the Stoke manager, said simply: "He changed the game."
Things had been looking desperate for Arsenal, who won 1-0 against Marseilles in the Champions League, thanks to a stoppage-time winner from Aaron Ramsey. He was one of the few players to rise above the ordinary here. But there may be a good reason for that. Playing Stoke brings with it particularly bitter memories for the Welsh midfielder. It was at the Britannia Stadium early last year that his career looked in doubt after he broke his leg in a challenge with Ryan Shawcross. Now he is fully fit and stood out ahead of the likes of Mikel Arteta and a stodgy-looking Theo Walcott with his range of movement and passing.
Ramsey set up Gervinho's goal that gave Arsenal the lead. His neat lob found the Ivory Coast international unmarked near the penalty spot, and he beat Asmir Begovic with ease. Yet Stoke regained parity seven minutes later in a manner typical of both the Potters and Arsenal. After Peter Crouch was fouled by Laurent Koscielny, the former Tottenham striker was on the end of a well-worked free-kick. Dean Whitehead, Matthew Upson and Jonathan Walters all kept the ball in the air long enough to find Crouch, who tapped in from a yard.
That strike worried Wenger. "We got nervous at 1-1 and that was down to frustration," he said. "We were in no-man's land with the goal. The players knew at half-time that they had been caught for the goal."
But then the Van Persie show started. His first came when Gervinho burst into the area and he found the Dutchman, who squeezed his shot past Begovic at the near post. Nine minutes later, after a move involving Andrei Arshavin and Gervinho, Van Persie had his second – and his 30th goal in 36 league and cup games since January – with a shot that squirmed in.
"Robin deserves massive credit," said Wenger. "The problem in the second half was to score goals but Robin can do that better than most players."
Booked: Stoke Whitehead, Wilkinson
Man of the match: Van Persie
Referee: L Mason (Lancashire)