Two down, one to go.
If this is the week that will define Arsenal's season, then Arsene Wenger can be extremely optimistic.
They brushed Liverpool aside with an impressive victory to take them five points clear at the top of the Premier League.
Then Arsenal traveled to Germany, soaked up everything Borussia Dortmund had to throw at them for an hour and took a remarkable win to leave them well-poised to qualify for the Champions League knockout stages.
Now comes Sunday's trip to Manchester United, where, in keeping with the two previous results, this is a chance for Arsenal to make another big statement.
They kicked off their week of destiny with accusations that they had yet to play anyone decent. Quite how Tottenham, beaten at the start of September, feel about that is anyone's guess.
Now they have beaten Liverpool -- second in the table before coming to the Emirates -- and Dortmund, who were runners-up in last season's Champions League and had won all their home games in the competition since December 2011, a run that included wins over Real Madrid and Manchester City.
But here come Manchester United. Traditionally the marker in any title race. They normally either are champions or, if you finish above them, you win the league.
That's why this game is so big for Arsenal. If there were any doubters after Dortmund, winning at Old Trafford would put the Gunners 11 points ahead of the champions and demonstrate to the rest of the Premier League that Arsenal are the real deal.
Arsenal will be drained after Dortmund. But United also had a grueling Champions League trip to Real Sociedad, although they will have an extra 24 hours to recover.
Arsenal are playing with confidence, belief and style, but United's start has been indifferent, even though their results are now slowly starting to improve under David Moyes.
The midfield is where Arsenal are strong. Mesut Ozil, Aaron Ramsey and Santi Cazorla are on fire. If Mathieu Flamini comes back in for Tomas Rosicky, Arsenal will have a strong anchor with Mikel Arteta also protecting the back four.
Ramsey's goals, Cazorla's work rate and Ozil's moments of magic make them tick in midfield, plus the defence looks solid and Olivier Giroud gets better with every game.
Make no mistake. Arsenal look like genuine title contenders. And the key is that the belief is growing throughout the ranks.
Wenger has tried to play down expectations. Now the hopes and ambitions are rising with every impressive result and victory.
But this is the real test. Victory at Old Trafford and suddenly the doubters and sceptics would surely have run out of reasons not to believe.
United are not the team they once were. Old Trafford is no longer a fortress. But beating United there will still take some doing.
Don't forget, Arsenal won at Old Trafford on the way to winning the title in 1998 and clinched it there in 2002. They had a let-off with Ruud van Nistelrooy's missed penalty in the Invincibles season of 2003-04.
Results and performances at places such as Old Trafford define teams. Win there and it shows you are strong enough to win the title. If Arsenal can deliver in United's own backyard, there really will be no stopping them.
Two down, one to go.