Arsenal have completed the signing of Japanese right-back Takehiro Tomiyasu from Bologna for £19.8m.
This is just as Hector Bellerin departed the Emirates for Spanish outfit, Real Betis, on a season-long loan deal.
The 22-year-old has signed a four-year deal with Arsenal, with the option of a fifth.
The Gunners will pay an initial fee of around £17million – plus £2.5m in easily achievable add-ons to Bologna.
The Japan international is primarily a centre-back but also provides cover at right-back.
Arsenal head coach Arteta told the club’s official website, "Takehiro is a strong defender with good experience in Serie A and at international level.
"He’s a versatile defender with great defensive qualities, high technical ability and composure on the ball. He will be an important member of our squad.
"We look forward to Takehiro joining up with us when he returns from international duty."