Career
Early years
Avlonitis started as an amateur in his hometown team Chalkineo Evias in which he played in the local league. In 2007 he was signed to Egaleo, which for three seasons played in Football League. In the 2008/09 season he was loaned to Ilisiakos.
In 2010 he signed to Kavala, where he played the 2010/11 season.
After the involvement of the club President Psomiadis in a match-fixing scandal, Avlonitis was released and signed a contract with Panionios. Olympiakos F.C.
In July 2014, Olympiacos announced the transfer of Avlonitis from former club Panionios for a fee of around €670.000.
On his first derby game against Panathinaikos, on the 26th October 2014, Avlonitis scored the winning goal for Olympiacos, as they beat Panathinaikos 1-0 at home. On 30 January 2015, the Austrian club Sturm Graz have expressed an interest to sign Olympiakos defender on loan.
The Greek defender is not in Marco Silva"s plans and Sturm Graz are moving towards to clinch a loan deal until the end of the season.
Eventually, the central defender will continue his career in Austria for Sturm Graz, on loan until the end of 2015-2016 season. On 6 February 2016, he made his debut with the club in a 2-2 away draw against South Carolina Rheindorf Altach. He was also a former Greece under-19 international.