Arsenal have signed Gabon striker Pierre-Emerick Aubameyang from Borussia Dortmund for a club record £56m.
The Gunners had two bids for Aubameyang rejected by Dortmund before agreeing a fee that eclipses the £46.5m they paid for Alexandre Lacazette in July.
Arsenal said the 28-year-old - the 2015 African Footballer of the Year - had joined on "a long-term contract".
Dortmund agreed to the sale after striking a deal to sign Chelsea forward Michy Batshuayi on loan.
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Aubameyang said: "I'm really happy to be here in this great team.
"The club has such a big history and great players like Thierry Henry. He's an example for us strikers. I'm a fast player and I score goals too, like Henry a little bit. I think I have to work a lot to be like him, but I will do.
"I hope that we will come back to the top as soon as possible. I will do my best to join in."
Aubameyang scored 141 goals in 213 games for Dortmund, including 21 in 24 matches this season.
But he was suspended by the German club for their match against Wolfsburg on 14 January for missing a team meeting.
The forward was also left out of the squad for their next game game at Hertha Berlin because club officials felt he was not focused enough, but he played 90 minutes in Sunday's 2-2 draw with Freiburg.
After his move to Arsenal was confirmed, Aubameyang called himself "a crazy kid" in a message to Dortmund fans posted on Instagram, also apologising for the manner of his departure.
"First of all, sorry for everything that has happened in the last month, but I already wanted a transfer last summer, it did not work out, but now it had to be," he said.
"Maybe it was not the best way for me to choose, but everyone knows that Auba is crazy - and yes, I am a crazy kid.
"I've made mistakes, but never with malice."
Aubameyang - who will wear the number 14 shirt at Arsenal - joined Dortmund from French club Saint-Etienne in 2013.
The only major trophy he won at Dortmund was the German Cup in 2017.
He was named Bundesliga player of the year in 2016, and last season was the German top flight's most prolific scorer with 31 goals.
He has played 56 times for Gabon, scoring 23 goals.
Aubameyang's impressive stats
- He averaged 116 minutes per goal in his time in the Bundesliga, a rate only Bayern Munich's Robert Lewandowski bettered in the same period (107 minutes per goal)
- He contributed to 172 goals in 213 matches in all competitions for Dortmund, averaging a goal or assist every 96 minutes
- He scored 66 goals more than any other Dortmund player since his debut in July 2013
|Aubameyang club-by-club league goals|
|Borussia Dortmund (2013-18)||144||98|
'Criminally overlooked' - analysis
German football expert Raphael Honigstein on BBC Radio 5 live's Euro Leagues Football Show
Aubameyang is somebody who will definitely add goals for Arsenal but I don't know if individually he will lift the team to another level. He's not that kind of player.
He definitely brings pace, finishing and movement. I think he's been criminally overlooked by some of the bigger clubs who might have wanted a more orthodox number nine.
He will add quality up front, there's no doubt about that, but I think it will be hard to play him alongside Lacazette as they are very similar in terms of position and movement.
Arsenal have lost Alexis Sanchez and his energy when he is on it, his pressing. I think you can sometimes underrate or not value enough the importance of somebody pressing from the front line. It's very contagious and acts as a trigger.
Aubameyang doesn't really do it. What Arsenal gain in terms of quality and pace, they might lose in terms of aggression.
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