In the same group, FC Zurich came from behind to beat Apollon Limassol 3-1, with Farley Rosa breaking the deadlock midway through the first half, but the Swiss outfit scored thrice thereafter to secure a comfortable victory.
Group B saw HJK narrowly defeat Copenhagen 2-1, Per Nilsson equalising in the 89th minute and Macoumba Kandji scoring the winner deep into injury time, while Torino and Club Brugge played out a goalless draw.
However, Tottenham Hotspur remain just behind, securing progression to the next round, following their narrow 1-0 win at home to Partizan Belgrade, with Benjamin Stambouli scoring the winner early in the second half.
The game at White Hart Lane encountered controversy when three pitch invaders, entering the field of play on separate occasions, caused the referee to take the players off the pitch for around fifteen minutes.
Celtic went down to a 3-1 defeat at home to Red Bull Salzburg, causing the Glasgow side to slip below their Austrian opponents off the top of Group D, while Astra Giurgiu secured a 1-0 win against Dinamo Zagreb.
Results in full: FC Zurich 3-1 Apollon Limassol, Villarreal 2-2 Borussia Monchengladbach, HJK 2-1 Copenhagen, Torino 0-0 Club Brugge, Asteras Tripolis 2-2 Besiktas, Tottenham 1-0 Partizan, Astra Giurgiu 1-0 Dinamo Zagreb, Celtic 1-3 Red Bull Salzburg, Estoril Praia 3-2 PSV, Inter Milan 2-1 Dnipro Dnipropetrovsk, St Etienne 1-1 FK Qarabag body check tags ::