First, the positive spin. Arsenal will travel to Madrid next Thursday for the Europa League semifinal second leg in the Wanda Metropolitano with hopes still alive of a place in the final after a 1-1 draw with Diego Simeone's team at the Emirates.

Atletico, the tournament favourites, had been tipped to finish off this tie at the first attempt by exploiting Arsenal's weaknesses in ruthless fashion. But they didn't -- and here comes the dose of negative realism -- because despite facing 10 men for more than 80 minutes, Arsenal could not take advantage of the gilt-edged opportunity that had been staring them in the face.

Wenger's team passed the ball around, repeatedly got behind the Atletico defence, dominated possession and kept the visitors penned in their own half for virtually the entire game. But the end result was 1-1 because Arsenal missed a host of chances and Atletico, through Antoine Griezmann, scored with pretty much their only real opportunity of the game.

This tale of woe is nothing new to Arsenal. It has been a long time now since Wenger's Invincibles won the Premier League in such emphatic style in 2004 before going close to winning the Champions League in 2006, when they lost the final against Barcelona in Paris after losing goalkeeper Jens Lehmann to an early red card.

That Arsenal team knew how to finish off an opponent. It was a team that showed no mercy, but they could also defend well enough to keep the back door firmly bolted shut.

If that was Arsenal at full strength under Wenger, this team is Wenger-lite, and their shortcomings are why few will give them any hope of getting the result they require next Thursday to make it to the Europa League final in Lyon and extend Wenger's 22-year reign by one more game.

Wenger himself voiced his frustration at the inability of his players to do what his greats were able to do without even thinking.

"The result is not in line with the performance," Wenger said. "Against a team who defends well, after going 1-0 up, our task was not to concede on the long ball.

"They couldn't score with a combination, they could only do it with a long ball, so we have to look at ourselves. The only chance they could have was on the long ball.

"We can only look at ourselves. We had 20 shots on goal, against Manchester United we had 23 on goal, but lost. We had the chances to win.

"So we come out of tonight with a bitter taste because we had the chances to already be in the final."

Wenger is right. Arsenal should have won this game emphatically enough to make next Thursday's second leg a mere formality.

The 10th-minute sending off of midfielder Sime Vrsaljko reduced Atletico to 10 men and, although Simeone's well-drilled team is perhaps the best-equipped in Europe to ride out a storm with a one-man disadvantage, Arsenal possess the attacking players to pick holes in any defence.

But that is part of the problem. They can pick holes in defences, but when the heat is on against top teams, they are not good enough to do the final bit by putting the ball into the net. Arsenal are world beaters on the edge of the opposition penalty area; they just fall apart like a jigsaw when they are in the box.

And the same applies at the other end, where their inability to defend properly has cursed them for longer than any Arsenal supporter cares to remember.

As Wenger pointed out, his defenders had just one job after Alexandre Lacazette had given Arsenal the lead: avoid being caught out by a long ball. Yet that is precisely what happened, with Griezmann taking full advantage by out-muscling Laurent Koscielny before scoring, just as Shkodran Mustafi fell over himself as he attempted to clear on the line.

It was a goal that has been played out so many times over recent years at Arsenal, with Wenger's team conceding just seconds after being in the opposition penalty area.

But when you cannot take your chances and also concede sloppy goals, you are never going to overcome the best teams. It has gone on for too long now, so it is no surprise that Wenger's last chance of a trophy with Arsenal has been placed in jeopardy by the two biggest failings of the second half of his reign.

Bad defending and wasteful finishing have held back Arsenal and Wenger, and they have now combined to make winning the Europa League so much more difficult.