After their 1-2 loss at home to Bournemouth last week, West Ham United were looking to pick up at least one point from their struggling London rivals, Arsenal, in the third fixture of the new 2018/19 Premier League campaign.
It looked very promising for the Hammers after Marko Arnautovic's 25th-minute opener, but only five minutes later Nacho Monreal has equalised following some bounces after Hector Bellerin's cross.
The final result was finished up by Danny Welbeck in the 92nd-minute after a very unfortunate own goal that came in the 70th-minute from young Hammers defender Issa Diop.
The battle of two new systems
After defensively struggling in their first two fixtures, both Unai Emery and Manuel Pellegrini were not going to step down from their newly implemented play systems that aren't perfectly working, at least for now.
Very high defensive line was causing all sorts of problems for both sides, but it was Arsenal who got the best of their chances scoring two goals and creating a chance that lead to an own goal.
However, the result could be much different after Robert Snodgrass and Michail Antonio missed one-on-one opportunities that could see West Ham being 1-2 up.
Former Arsenal forward Lucas Perez also missed a good chance to bring West Ham level after coming on from the bench as a substitute.
Has the perfect setup been finally found for the Hammers?
Despite the defeat, there are much more positives than negatives to be taken out from today's display.
Łukasz Fabiański has yet again shown his goalkeeping qualities saving West Ham on multiple occasions, Arthur Masuaku and Ryan Fredericks looked dangerous running forwards as well as being solid at the back when covering the sides from the likes of Pierre Emerick-Aubameyang, Alex Iwobi or Alexandre Lacazette.
The first team debutants Carlos Sanchez and Issa Diop were also showing promise for the future as the Colombian was looking strong defensively and was holding the back line very well from the defensive midfield spot with the young Frenchman putting in some strong tackles - before conceding the earlier mentioned own goal.
Felipe Anderson has finally shown the fans a big chunk of his talent after being a pain for Arsenal's defence through the game because of his powerful forward runs from the central attacking midfield position.
The Brazilian attacker also picked up an assist for the only goal scored by the Hammers.
Injury worries for the forward ace
Arnautovic's fitness levels has already been questioned last week, but now he might be out for quite some time leaving Pellegrini with an unwanted problem in the buildup to the game against the newly promoted Wolves, that will take place in two weeks time.
After being down few times during the game with a knee struggle, the Austrian finally needed to be substituted out in the 59th minute, which saw West Ham struggling to finish chances and finally fall down under Arsenal's constant pressure.