Arsenal have completed the signing of David Luiz from rivals Chelsea on deadline day in England on Thursday after the Brazilian expressed a desire to leave Stamford Bridge this week.
Luiz, 32, began his career with Benfica and has since played for Chelsea twice, while he also had a spell at Paris Saint-Germain, where he played under Arsenal coach Unai Emery. He has also played 56 times for Brazil.
"David has a lot of experience and I am looking forward to working with him again," Emery said. "He's a well-known player and he's going to strengthen our defence."
Arsenal also announced the signing of Scottish left-back Kieran Tierney from Celtic on Thursday.