Alexis Sanchez scored at the end of each half to help Arsenal to a comfortable 2-0 victory over Sunderland.
The Chilean forward capitalised on defensive errors from Wes Brown, in the first-half, and Vito Mannone, in the second-half, to take his Premier League goal tally to five in eight appearances.
After the match, Alex Oxlade-Chamberlain couldn't hide his appreciation and delight of his teammate's impact and labelled Sanchez as ''an unbelievable player''.
''He's a world-class player - everyone saw that at the World Cup,'' said the 21-year-old.
''He's proved that and he's played for Barcelona where we've all seen what he's done.
''He reminds me of Luis Suarez when he chases everything down and he makes nothing into something. He's done that for us twice today and he's scored goals at important times for us.''
Sanchez, who signed for Arsenal for a fee in the region of £35million from Barcelona in the summer, was effectively replaced by former Liverpool striker Luis Suarez at the Catalan club.
The Chilean international scored goals at an alarming rate in Spain but never seemed to fit into the Barcelona ethos and was, rightly or wrongly, moved out in favour of mega-deal for Luis Suarez during the summer transfer window.
19 goals and 10 assists weren't enough to keep the Barcelona chiefs happy and once Arsenal made their move on Sanchez, Barcelona made their move on Suarez.
The tenacity of Sanchez has certainly helped him adapt to life in the Premier League quickly and, baring injury, he should be able to make a huge impact on where Arsenal are to finish at the end of the season.