With their previous European tie, way back in 1958, ending in a walkover victory for Beşiktaş, Olympiacos and the Black Eagles are set for their first competitive encounter in the UEFA Europa League round of 16 today. Although the teams are meeting for the first time in UEFA competition, they had been drawn together in the preliminary round of the 1958-1959 European Champion Clubs' Cup, where Olympiacos withdrew due to political problems between Greece and Turkey, and Beşiktaş progressed to the first round (where they lost to Real Madrid).The clubs though have contested in friendly matches for the last two summers, where Olympiacos won 2-1 in 2015 and Beşiktaş triumphed 1-0 in 2016.Olympiacos have so far played five matches against Turkish sides in UEFA competition, registering two wins, one draw and a solitary loss (W1 D1 in Greece - W1 L2 in Turkey). In the round of 32 this season they brought down Osmanlıspor 3-0 in Turkey, after a goalless first-leg draw.On the other hand, Beşiktaş's two previous UEFA meetings with Greek sides had both ended in stalemates, 1-1 at home and 2-2 away against Asteras Tripolis in the 2014-2015 UEFA Europa League group stage.This will be the only be the second instance where the reigning champions of Greece and Turkey meet in UEFA competition, following Galatasaray's 1-0 home win against Olympiacos in the 2008-2009 UEFA Cup group stage. The Turkish table toppers have scored in 16 of their last 17 European fixtures, with the exception of a 6-0 loss at Dynamo Kiev, in their final group game in this season's UEFA Champions League.Meanwhile, Olympiacos' last two European home games ended in draws, first, 1-1 then 0-0. They have reached the round of 16 for the first time since 2011-2012, having fallen at their first springtime hurdle in the last four seasons. They have never made it to the last eight in this competition but advanced to the quarter-finals of the European Cup Winners' Cup in 1992-1993 and the UEFA Champions League in 1998-1999.The nearest Beşiktaş have ever come to lifting a major European honor was when they reached the last eight of the UEFA Cup in 2002-2003 and the European Cup quarter-finals way back in 1986-1987.