Arsene Wenger will take his summer spending past the £50m mark this week after finalising moves for £3.2m Colombia goalkeeper David Ospina and £12m Southampton teenager Calum Chambers.
They will join £32m Chile forward Alexis Sanchez, signed from Barcelona, and Newcastle's £12m defender Mathieu Debuchy at the Emirates.
Ospina, who has been awarded a four-year contract, will put pressure on Arsenal first-choice Wojciech Szczesny, but will not start the season as first choice.
The 25-year-old caught the eye with his performances for Colombia in the World Cup, but Wenger insists he has been tracking the 25-year-old for a while.
"I've known Ospina for a long time because he plays for Nice," the Arsenal manager said. "He went there a few years ago and slowly became a very important player.
"You can see he has quality because Hugo Lloris played for Nice before and after he moved to Lyon they got Ospina. And Llorris is not an easy player to replace.
"I think he also did very well at the World Cup. We had three or four candidates and I decided to sign him during the World Cup."
Wenger said he can also understand the shock at such a fee for the inexperienced Chambers, who has made only 18 Premier League starts for Southampton, but he likes the 19-year-old's versatility.
He added: "He can play at centre-back, right-back and central midfield. I hope he will give us competition for the players in these positions.
"He hasn't played many games, no, but the English players on the market in England are very expensive and at the end of the day I was ready to take a gamble because he is a player for the future."
Arsenal's skeleton squad flew straight back from America on Saturday night after an opening pre-season defeat by Thierry Henry's New York Red Bulls.
Wenger takes the bulk of his squad, including his French World Cup players, to Austria today for an intensive training and bonding camp.