Swansea recorded the most remarkable victory in their history when they eased past Valencia at the Mestalla in their Europa League opener, while Spurs saw off Tromso.
Swansea recorded a famous win in Valencia, seeing off the Spanish side 3-0 in their opening game in Group A of the Europa League.
The Spanish outfit got off to the worst possible start as Adil Rami saw red for bringing down Wilfried Bony, who had a clear run on goal.
The Swans made their opponents pay just minutes later with a first-half strike from Bony, before Michu doubled the advantage in the second half and Jonathan de Guzman then curled home a stunning free-kick.
St Gallen are level on points with the Swans at the top of Group A after they beat Kuban Krasnodar 2-0 thanks to second-half goals from Goran Karanovic and Marco Mathys. The Russian club saw Charles Kabore sent off deep into injury time.
A Jermain Defoe brace and a superb Christian Eriksen strike gave Tottenham a 3-0 win against Tromso at White Hart Lane.
However, the victory came at a cost as Mousa Dembele, Danny Rose and Younes Kaboul all came off through injury.
In the other game in Group K, Sheriff Tiraspol played out a 0-0 draw with Anzhi Makhachkala.
FA Cup winners Wigan emerged from their first-ever European match with a point after battling out a 0-0 draw with Zulte Waregem in Bruges.
Roared on by around 2,500 fans who had made the trip from Wigan for the Group D game, the Championship side survived the pressure at a sodden and sparsely-populated Jan Breydel Stadium to claim a draw.
Rubin Kazan went to the top of Group D as they won 5-2 at NK Maribor, with Salomon Rondon and Alexander Ryazantsev netting late goals for the Russian side to make sure of the win.
Kevin Gameiro emerged from the bench to fire Sevilla to a 2-1 victory at Estoril in Group H.
The Spanish side toiled for an hour in Portugal before Vitolo made the breakthrough, but Estoril hit back immediately through Bruno Miguel. Gameiro, a summer signing from Paris St Germain, then scored the decisive goal.
In the same group, a second-half resurgence from Liberec saw them claim a 2-2 draw at Freiburg .
The Bundesliga side were dominant for an hour and eased into a 2-0 lead before half-time but the game changed in the last half-hour as Vladislav Kalitvintsev and Michael Rabusic cancelled out Julian Schuster's penalty and Admir Mehmedi's follow-up.
There was no winner, but both sides suffered red cards as Karim Guede and Sergiy Rybalka exited before full-time.
Fiorentina made a winning start to their Group E campaign with a 3-0 defeat of Pacos de Ferreira in Italy.
Gonzalo Rodriguez put the Italians on their way on the half-hour mark before substitute Ryder Matos extended Fiorentina's lead in the 67th minute. Giuseppe Rossi then made it 3-0 with 14 minutes remaining.
They were joined at the top of Group E by Dnipro Dnipropetrovsk, who won 1-0 at Pandurii Targu-Jiu thanks to a first-half goal from Ruslan Rotan.
Hernanes's second-half goal earned Lazio a deserved 1-0 victory at home to Legia Warsaw in Group J.
The Brazilian midfielder headed Balde Keita's cross past helpless Legia goalkeeper Wojciech Skaba in the 53rd minute to earn his team all three points.
Substitute Yusuf Erdogan snatched a late winner as Trabzonspor launched their mission to make the grade in Group J with a 2-1 win at Apollon Limassol.
PSV Eindhoven went down to a shock 2-0 home defeat against Ludogorets Razgrad in Group B.
PSV dominated the first half but were stunned after the break as Roman Bezjak and Virgil Misidjan both scored to secure victory for the visitors.
There was another upset in Group B as two goals in three second-half minutes gave Chornomorets a 2-1 win over Dinamo Zagreb.
Junior Fernandes gave Dinamo the lead but goals from Oleksiy Antonov and Franck Djadjedje turned the game on its head and gave the Ukrainians victory.
Eintracht Frankfurt eased to a 3-0 victory in their Group F opener against Bordeaux to make it five wins from their last six matches in all competitions.
The German side brushed aside their Ligue 1 opponents with apparent ease, with Vaclav Kadlec, Marco Russ and Constant Djakpa all on target in the opening hour.
In the same group, Maccabi Tel-Aviv drew 0-0 at home to Apoel Nicosia as Barach Yitzhaki missed a last-gasp penalty for the Israeli club.
Johann Berg Gudmundsson scored the only goal as AZ Alkmaar picked up an impressive 1-0 win at Maccabi Haifa in Group L.
Shakhter Karagandy were the victims of late drama in European competition again as PAOK Salonika won 2-1 with an injury-time goal in their Group L clash.
The Kazaks were good bets to make the Champions League proper until Celtic fought back to beat them last month, and they were given a similar medicine in the Europa League.
Jonathan Soriano scored a hat-trick as Salzburg secured a 4-0 victory over Elfsborg in Group C.
After Brazilian striker Alan opened the scoring at the Red Bull Arena, Soriano notched a first-half penalty before adding two more goals from close range after the interval.
Group C rivals Esbjerg got the better of Standard Liege, winning 2-1 thanks to Mushaga Bakenga’s goal deep into stoppage time, meaning they and Salzburg have sole ownership of top spot.
Substitute Julien Gorius scored the only goal as Racing Genk got their Group G campaign off to a good start with a 1-0 win away to Dynamo Kiev, while FC Thun join them at the top after they beat Rapid Vienna by the same scoreline.
Information from the Press Association was used in this report.