Goals from Nacho Monreal and Alex Iwobi took Arsenal to a 2-0 Premier League victory against Albion this afternoon. Here's six things we learned from the game.
Plenty to take
There were plenty of positives for Brighton to take, although they were disappointed with the goals they conceded afterwards.
Arsenal started strongly but Albion began to look bright going forward after falling behind and had a few opportunities to score. Solly March continued to impress in the Premier League and went close to an excellent equaliser when his 25-yard strike came back off a post.
Shane Duffy and Lewis Dunk were again solid in central defence and threw their bodies in the way of several shots, while goalkeeper Mathew Ryan made a string of fine saves.
Today's game was Albion's second real big test of the season, after Manchester City on the opening day. Against City, Albion had just 22 per cent of possession and rarely looked like scoring.
Brighton caused Arsenal more problems going forward and that will give them confidence when they travel to the rest of the big sides later in the season.
Look after the ball
Too often in the first half, Albion gave the ball away too easily. Yes, they were against an Arsenal side with a lot of quality but the Seagulls still had opportunities to look after the ball much better than they did.
A number of the passes that went astray were when the players were not under too much pressure.
When Albion did get the ball down and play, they looked threatening going forward at times. With a bit more luck in the first half, Solly March's first half strike, after a clever free kick routine, would have drawn Brighton level.
Punished for small mistakes
The step up in class to the Premier League was again highlighted on a couple of occasions today.
For the main part, Albion played well - they were solid in defence and looked bright going forward. However, a rash challenge by Jose Izquierdo on Alexandre Lacazette was punished as Arsenal scored from the resulting free kick.
Shkodran Mustafi and Hector Bellerin had shots blocked, before Nacho Monreal fired home. You could question whether Izquierdo needed to make the challenge but it will be a moment the Columbian winger will learn from on his first Premier League start.
Take your hat off
Sometimes there just isn't much you can do to stop the opposition from scoring.
Albion were more than holding their own at the Emirates, trailing to Nacho Monreal's first half strike, approaching the hour mark when the Gunners doubled their lead.
Alexis Sanchez was becoming more and more prominent in proceedings and it was no surprise he was involved in Arsenal's second.
Quick link-up play between Aaron Ramsey and Sanchez ended with the Chilean winger playing a lovely back-heeled pass into Alex Iwobi's path and he made no mistake as he fired home from 15 yards.
Could Albion have defended better? Maybe. But sometimes you just have to take your hat off and appreciate a bit of world-class skill from Sanchez.
There was also another piece of world-class skill early in the game. Alexandre Lacazette, who cost the Gunners £54m from Lyon in the summer, crashed an effort against a post inside 70 seconds with a wonderful 25-yard strike. By the end, however, the French striker had failed to score in a Premier League game at the Emirates for the first time this season.
Arsenal increased their unbeaten run against newly-promoted sides to 32 games.
Chris Hughton was the last newly-promoted manager to win a game at the Emirates, 1-0 with Newcastle in 2010 when Andy Carroll got the only goal.
The Seagulls made three changes from the 1-0 win against Newcastle last week. Tomer Hemed missed out through suspension, which meant Izzy Brown played the lone striker role. Gaetan Bong replaced Markus Suttner at left-back and Jose Izquierdo made his first league start.
On the bench, Glenn Murray was named as a substitute after struggling with an ankle injury since the 2-0 defeat at Leicester, while young Irish midfielder Jayson Molumby was named in a Premier League squad for the first time.
Another option up top
With Tomer Hemed suspended, Glenn Murray only on the bench and Sam Baldock out, Chelsea loanee Izzy Brown played the lone striker role.
It was the 20-year-old's first appearance since the opening game of the season when he limped off with a hamstring injury against Manchester City.
Brown had impressed in pre-season for Albion and again did not let the side down as he held the ball up well with some nice touches.
He played a big part in Huddersfield's promotion to the Premier League last season and you get the feeling he will be a key figure as Albion bid to stay in the top flight. He can play in a number of positions and will likely be used as one of the wingers in away games when Hemed or Murray are back starting games.