Valencia have one foot in the Europa League quarter-finals, while Portuguese duo Porto and Benfica also won well. Elsewhere, Germany international Mario Gomez ended his goal drought with a crucial strike for Fiorentina.
The first leg of the Round of 16 threw up as many questions as answers, but in good shape are 2003-04 Europa League winners Valencia, fellow Spanish club Real Betis, Benfica and Lyon of France. Their opponents - Ludogorets of Bulgaria, Spanish club Sevilla, English outfit Tottenham and Czech underdogs Viktoria Plzen - face a mountain of work in the second leg of their respective ties on March 20.
Porto and AZ picked up 1-0 home wins, while Juventus and Fiorentina drew 1-1 and Basel's hosting of Salzburg ended in a 0-0 stalemate.
Away to Ludogorets, Valencia's route to a 3-0 win began in the fifth-minute lead, when right-back Antonio Barragan scored with a first-time shot from outside the area.
Valencia suffered a brief setback in the 24th minute when midfielder Seydou Keita was sent off. The Malian deserved to concede the penalty for clattering into Roman Bezjak but not the red card as the last man, with team mate Philippe Senderos in a covering position.
Bezjak could not beat a diving Diego Alves in Valencia's goal, however, and Ludogorets were made to rue the miss when Federico Cartabia made it 2-0 for the visitors eight minutes later.
The tie was all-but put to bed when Senderos nodded home on the hour mark, and a poor night for the hosts was completed when Juninho Quixada was sent off.
Super Mario in Turin
A German had an important say in an all-Italian battle in Turin. Former Bayer Leverkusen man Arturo Vidal helped hosts Juventus take a third-minute lead against Fiorentina, with an entertaining arm-wrestle ensuing thereafter.
The status quo was restored in the 79th minute when Gomez found the net. On as a substitute just 12 minutes earlier, the striker took a deft touch from a ball over the defense at full pace before shooting inside Gianluigi Buffon's near post to make it 1-1. The relief was clear on the 28-year-old's face. After all, it was just his third goal for the Serie A outfit since moving from Bayern Munich in July, and it also could prove crucial come his team's home leg.
Action Jackson hands Porto advantage
The first half of Porto's hosting of Italian outfit Napoli was forgetful rather than fascinating. Soon after the break, Gonzalo Higuain - by foot - and Raul Albiol - by head - went close within moments of each other. Both were thwarted by saves from the Portuguese club's goalkeeper Helton, and the breakthrough came down the other end.
From a Porto corner, Jackson Martinez's shot was deflected just enough by Albiol to beat Napoli shot-stopper Pepe Reina.
Porto - Eintracht Frankfurt's conquerors in the Round of 32 - could have had a crucial second close to the 80th minute, but one part sturdy Napoli defending and another part bad luck thwarted first Nabil Ghilas and then fellow substitute attacker Juan Quintero.
Spurs struggle at home
Tottenham slumped to a 3-1 win despite starting the brighter at home in their tricky tie with Benfica. They were hit with a sucker punch on 30 minutes when the Portuguese league leaders broke and scored through Spanish forward Rodrigo. Having soaked up Spurs' early pressure, Benfica must have been delighted to find the back of the net with their first effort of the match.
Spurs pushed for an equalizer, but again conceded thanks to some poor defending - this time in the 58th minute, when Luisao rose unmarked to head home from a corner.
Attacking midfielder Christian Eriksen pulled on back six minutes later with a superb free-kick, but Spurs' defending haunted them a third time on 84 minutes to allow Benfica captain Luisao his double - again from a corner
Stalemate in Basel
In Switzerland, neither Basel nor Salzburg could find a breakthrough. Occasionally ill-tempered and always fiercely contested, Austrian club Salzburg will be content to take a 0-0 result home for the second leg. They did test Basel goalkeeper Yann Sommer on more than one occasion, but the Switzerland international - to join Bundesliga club Borussia Mönchengladbach for the 2014-15 season - kept his sheet clean.
Elsewhere, Lyon found themselves behind just three minutes into their home match with Plzen, but recovered to win 4-1. There was an upset in Sevilla, with local rivals Real Betis snatching a superb 2-0 win. Finally, in the Netherlands, Aron Johannsson's deflected penalty was the difference in AZ Alkmaar's 1-0 win over Russian outfit Anzhi.