A product of
Al-Ittihad's youth system, Kalaji made his first-team breakthrough under manager
Valeriu Tița during the
2009–10 season. He played as a
midfielder, wearing the number 14 jersey for Al-Ittihad. He helped Al-Ittihad reach the
final of the
AFC Cup the second most important association cup in Asia. Al-Ittihad won the final against
Kuwaiti Premier League champions
Al-Qadsia after penalties. The game was tied 1–1 after regular time and Extra Time. He later played abroad on loan for
Al-Muharraq and
Manama Club in Bahrain,
Sulaymaniya in Iraq, and
Nejmeh in Lebanon. He subsequently joined
Al-Jaish in 2017, where he achieved three consecutive
Syrian Premier League titles. He then played for
Hutteen,
Afrin, and had another stint with Al-Jaish in 2022. ==International career==