What a dreadful week for English clubs in the Champions League.

One team got their tactics wrong, the other lacked leadership and authority on the pitch as they tossed away a lifeline.

Let’s start with Manuel Pellegrini.

He won the title in his first season as Manchester City manager and is tactically more literate than I will ever be.

So how on earth he believed the best way for City to beat Barcelona on Tuesday was by playing 4-4-2 is absolutely beyond me. I thought 4-4-2 in Europe went out with the dinosaurs.

City were knocked out of the Champions League against Barcelona last season without laying a glove on them at the Etihad.

Maybe Pellegrini was determined to have a proper go at them this time. But if punters on Twitter, TV pundits and armchair viewers at home could see City would surrender the midfield by playing 4-4-2, why couldn’t the most important man of all – the one who dictates the team’s shape and tactics?

If you are going to stand toe to toe with Barcelona, surely the best way is not to concede possession and give them acres of room in the middle of the park?

Some people think Barca are not quite the force of old from Pep Guardiola’s era. Pull the other one – a front three of Messi, Neymar and Suarez was never going to be a picnic.

The tie would have been a dead duck already if Joe Hart had not saved Lionel Messi’s penalty at the death which would have made it 3-1.

Man City 1-2 Barcelona in pictures:

Apart from Pellegrini’s naive game plan, the biggest worry for me is captain Vincent Kompany’s form.

Pound for pound, Kompany has been one of the greatest signings in Premier League history. Mark Hughes signed him for £6million from Hamburg seven years ago and he has proved to be an absolute steal.

But although Kompany is still the club's strongest defender, at times he has looked vulnerable this season .

Another big worry is City’s transfer policy.

Since May 2012, they have spent £220million on 18 players – and you could argue that none has markedly improved Pellegrini’s strongest XI.

Look at the names:

Mangala, Fernandinho, Jovetic, Negredo, Garcia, Navas, Nastasic, Rodwell, Fernando, Sinclair, Caballero, Demichelis, Maicon, Zuculini, Lampard, Sagna, Wright, Bony.

Three of them have already been sold and another four have been loaned out.

Uncon-Vince-ing: Kompany's struggles this season continued against Barcelona

Of those 18 signings, I would argue that Frank Lampard – who is only ‘on loan’ from New York City – is a major influence now.

Their most important players – Yaya Toure, David Silva, Sergio Aguero and Hart – all won the title under Roberto Mancini.

Look at Chelsea, who now seem likely to be flying the flag for English football alone again in the Champions League beyond this round.

They signed Diego Costa and Cesc Fabregas last summer and immediately they raised the bar.

If Man City fans are wondering why they are making so little headway in Europe, maybe it’s because Pellegrini has been stocking the reserves without improving his first team.

As for Arsenal ...

A poor performance against Monaco , where nothing went right, ended in shambles.

The lack of leadership and authority on the pitch after Alex Oxlade-Chamberlain’s late goal had given the Gunners a foothold in the tie, was absolutely shocking.

At 2-1 down, if you go to Monte Carlo and score first, it’s game on.

But Arsenal’s response to pulling that goal back was suicidal.

Arsenal 1-3 Monaco in pictures:

There were players on that pitch in red shirts who have won the World Cup. Yet nobody had the force of personality to say, “Hang on, lads. We’ve given ourselves a chance here. Let’s not throw it away.”

And look what happened.

The kamikaze way Arsenal conceded that killer third goal made me despair that they will EVER learn to shut up shop.

Who calls the shots? Who takes responsibility? Who’s in charge?

Yes, I’m looking at you , Per Mertesacker.

And I felt keeper David Ospina should have done better with the last goal, too.

But ultimately, it’s Arsene Wenger in the firing line again , because this keeps happening to Arsenal.

Every year, like a Direct Debit on your bank statement, they qualify for the Champions League knockout phase but then, when the Holy Grail appears in the distance, they come up short.

Something has to change.