Sead Kolašinac was born on 20 June 1993 in Karlsruhe, Germany, to Bosnian parents who had emigrated during the Yugoslav wars. He came through the youth ranks of Stuttgart and then Hoffenheim before transferring to Schalke 04 in 2011, where he completed his development and broke into the senior squad.
Across six seasons with Schalke he played more than 150 Bundesliga matches, becoming the supporters' nicknamed "tank" for his bullish overlapping runs from left-back. In 2017 he joined Arsenal on a free transfer, where he won the FA Cup in 2017 and again in 2020 and was a regular under Arsène Wenger before falling out of favour under Mikel Arteta. After a loan back to Schalke he transferred to Marseille in 2022, and joined Atalanta on a free in 2023.
At Atalanta he has been a versatile defensive option — primarily as a left-sided centre-back in Gasperini's three-at-the-back system, but also capable of filling in at left wing-back. He was part of the squad that won the 2024 UEFA Europa League and the 2024 Coppa Italia, the most successful spell in the club's modern history.
For Bosnia and Herzegovina he debuted in 2013 and went on to captain the national team, with more than seventy caps. He played at the 2014 World Cup and Euro 2024 qualifiers and remains one of the country's most decorated defenders.
Standing 1.83 m and powerfully built, Kolašinac is a left-footed defender who combines aerial dominance, physicality and surprising long-distance passing range. His blend of toughness and overlapping willingness draws comparisons with Patrice Evra in his Manchester United pomp.