This will be Benfica's ninth major European final. After winning the first two (European Cup finals in 60/61 and 61/62) they have lost each of their last six.
Chelsea will be taking part in their fifth major European final, having won three so far, including last season's Champions League.
The two sides have only met on two previous occasions, in March and April last season in the Champions League, when the Blues won both games, 2-1 at home and 1-0 away.
Three of the four scorers in those games, Salomon Kalou and Raul Meireles for Chelsea and Javi Garcia for Benfica, are no long with their respective clubs (Frank Lampard, still with the Blues, also scored).
The Super Eagles have met English opposition in a European final before, when they were beaten 4-1 at Wembley by Manchester United in the 1968 European Cup Final.
Chelsea have suffered just one defeat in their eight previous clashes with Portuguese opposition, winning six (including each of the last five) and drawing one.
The Blues have shipped just one goal in their last four games against sides from Portugal.
Benfica, on the other hand, have registered just one victory in their last seven clashes with English sides; 3-1 at home to Newcastle in April.
In European competitions this season (excluding qualifiers), only PSG's Zlatan Ibrahimovic (7) has provided more goal assists than Chelsea's Juan Mata (6).
Victor Moses has netted in each of Chelsea's last four Europa League games (four in four).
Benfica hitman Oscar Cardozo has netted five in his last five Europa League fixtures.
Six of the Blues' last eight Europa League goals have come after the break.
