On 24 June 2017, Hajsafi signed a two-year contract with Greek Super League side Panionios. He is set to team up with fellow countryman Masoud Shojaei at Panionios. Hajsafi became the third Iranian in recent years to play for the club.
Hajsafi made his first appearance for the club on 13 July 2017 in a second round Europa League qualifying match against Slovenian club Gorica. On 20 August 2017, on his league debut with Panionios, Hajsafi recorded an assist from a corner kick.
On 29 December 2017, after six months with Panionios, Hajisafi reached an agreement with Greek side Olympiacos, signing a three and a half years' contract for a transfer fee of €600,000. His contract, was worth €400,000 per year. The 27-year-old player was the team's first transfer in the January window. On 11 February 2018, he made his debut with the club in the Superleague Greece as a starter, scoring a late goal as he bundled home the rebound to sealed a point for Olympiacos when Atromitos keeper Andreas Gianniotis saved Uros Djurdjevic’s penalty-kick.
On 10 August 2017, Hajsafi was banned from the national team, along with teammate Masoud Shojaei, for playing with their club Panionios against Israeli club Maccabi Tel Aviv. His ban was rescinded after posting a religious message on his Instagram. In May 2018 he was named in Iran's preliminary squad for the 2018 World Cup in Russia. He played his 100th international game on 15 November 2018 at the age of 28 in Azadi Stadium against Trinidad and Tobago.