Ospina will be expected to rival Szczesny for the starting spot in goal.
Ospina completed his move to the Emirates Stadium yesterday for an undisclosed fee from Nice after impressing for Colombia at this summer's World Cup in Brazil, where he helped his side reach the quarter-finals.
He told arsenal.com: "He is a great goalkeeper, very skilful. He has been a regular at a top side like Arsenal, so he is quality. We also have the Argentine goalkeeper Damien Martinez. They are both young players but very experienced."
Szczesny has been the first choice goalkeeper for Arsene Wenger since the 2010/11 season but Ospina is expected to challenge the Pole for the number one spot at the club, and Nice coach Claude Puel has even tipped him to shine for the Gunners.
Competition for the starting place is likely to be fierce given that both goalkeepers are at a relatively young age. Szczesny has had the pressure on him since a young age after starting to get regular games at the age of 20, but the 24-year-old is expected to raise his game given the signing of Ospina.
Ospina also fills a void that may have been left by Lukasz Fabianski, who was the second-choice goalkeeper last season, but had his fair share of game time. Fabianski has since left Arsenal in search of regular first-team football at Swansea City.
It will be interesting to see who manager Arsene Wenger opts for between 25-year-old Ospina, or the man who has kept goal for the past few years in Szczesny.