"I watched the little one when he was on loan in ČSK Čelarevo. It's unbelievable how he pushes the ball, like Iniesta. I thought he wouldn't be able to repeat that in the top tier, but he dominated here too. He's a scary player."
Plavšić played in FK Vojvodina's youth system, but was told that he was too small to make it for Vojvodina's first team.[2] He began playing football on a senior level with ČSK Čelarevo in the lower tiers of the Serbian football pyramid.[3][4] He played in Čelarevo for two seasons before moving to Spartak Subotica.[4] It was in Spartak where Plavšić made his debut in the Serbian top flight for the 2014–15 season, and he played impressively particularly in a match against Red Star Belgrade.[1]
Red Star Belgrade
On 10 August 2015 Plavšić signed a three-year contract with Red Star Belgrade. In his promotion the following day, he chose the number 17 for his jersey.[4] At Red Star, he got the nickname "Atomic Ant", due to his height of 166 centimeters, which at the time was the shortest among all of Red Star's players.[5] In the first half of the 2015–16 season, Plavšić was statistically Red Star's most fouled player, as other teams' players would routinely accumulate yellow cards from tackling him.[6]
Sparta Prague
Plavšić signed with Czech side Sparta Prague on 27 June 2017.[7] The reported fee is believed to be around €1.3 million.[8] He made his debut for Sparta in 2–0 defeat against his former club Red Star Belgrade on 27 July 2017.[9]
Slavia Prague
Plavšić signed a three-year contract with city rivals Slavia Prague on 10 June 2021.[10]
Loan to Baník Ostrava
On 8 September 2022 he was loaned to Baník Ostrava in Czech First League.[11]
Raków Częstochowa
On 25 July 2023, Plavšić was transferred to defending Ekstraklasa champions Raków Częstochowa, with whom he signed a three-year deal, with an option for another year.[12] He established himself as the first-choice left wing-back in the first half of the 2023–24 season before losing his spot to a winter arrival Erick Otieno. On 20 February 2024, Raków announced Plavšić had suffered a MCL tear during a training session two days prior.[13] Shortly after resuming training in early May, he ruptured his Achilles tendon, and is expected to be sidelined for the rest of the year.[14]
Plavšić's father Petar, also born in Novi Sad, was a professional futsal player during his youth.[6] Srđan has credited his father for teaching him many of the tricks he plays in matches.[6] Srđan's paternal grandfather is from Šipovo.[17]