After 16 years away, Levski Sofia return to the Europa League as they welcome Red Bull Salzburg to the Vasil Levski National Stadium on Matchday 1. The Bulgarian champions last featured in the 2010/11 Europa League group stage and now make their long-awaited return under the new format, whereas Salzburg are no strangers to this stage, having qualified for European competition for twelve consecutive seasons. The hosts have made an unbeaten start to their Parva Liga campaign, recording an 8-1-0 record, with their only stumble being a goalless draw at Botev Vratsa last time out. Their only defeat so far came in the Bulgarian Supercup where they were beaten by CSKA Sofia. As for Red Bull Salzburg, they have also started unbeaten, with a 4-2-0 record, their last outing being a 1-1 draw on the road at SV Ried, where they scored late in the day through Karim Konate before Ried rescued a point moments later. Salzburg made it to the league phase of this competition last season, where they were knocked out in 31st place with two wins from their eight games, coming against Go Ahead Eagles and Basel. They also led 2-0 at Villa Park before throwing it away and losing 3-2. Levski's campaign to get here started all the way back in July, when they knocked out Bosnian opposition Borac Banja Luka 5-1 on aggregate, before progressing past Universitatea Craiova and Kairat Almaty, only to be knocked out by AEK Athens in the Champions League playoff round. Salzburg, meanwhile, had a much shorter route to the league phase, entering in the Third Qualifying Round, where they narrowly saw off Pafos before cruising past Mjallby in the playoffs. Haris Tabakovic is a player to keep an eye out for in this game. The 32-year-old striker has nine goals in ten games since joining this summer, three of those coming in their 3-3 draw in Cyprus. For Levski, Armstrong Oko-Flex is the standout. The former Celtic & West Ham youngster has five goal contributions across eight league games so far this season. These clubs have met twice before, as they were put in the same group during the 2009/10 Europa League campaign. Salzburg won both of those games 1-0 and topped the group with a perfect 6-0-0 record. Salzburg will be without Gaoussou Diakite and Soumalia Diabate due to injuries while backup goalkeeper Christian Fruchtl remains a doubt following a foot injury. Levski will be without winger Radoslav Kirilov, who picked up an injury during the summer and has yet to feature so far this season. Akram Bouras is out due to a strain while centre-back Nikola Serafimov misses out due to a dislocated elbow and is set to be back after the international break.