Crystal Palace atoned for a Matchday 2 defeat against AEK Larnaca with a comfortable win against AZ Alkmaar, while Mainz snatched victory at home against Fiorentina in the UEFA Conference League.
UEFA.com wraps up the Matchday 3 action.
Crystal Palace 3-1 AZ Alkmaar
Crystal Palace rediscovered their goalscoring form after a blank against AEK Larnaca last time out, securing a first league phase home win. Maxence Lacroix and Ismaïla Sarr struck in the first half after AZ keeper Rome-Jayden Owusu-Oduro had saved a Jean-Philippe Mateta penalty and denied Sarr from close range. Sven Mijnans halved the lead, but Sarr finished a defence-splitting Mateta pass to secure three points and leave AZ with just one win from three games.
Mainz 2-1 Fiorentina
Simon Sohm converted Fiorentina's first meaningful chance on 16 minutes, and the side under the temporary leadership of Daniele Galloppa should have extended their lead by the break before a run of second-half substitutions revived Bo Henriksen's Mainz. Benedict Hollerbach levelled three minutes after coming off the bench and Kaishu Sano set up fellow replacement Jaesung Lee for a last-gasp headed winner to maintain the Carnival Club's 100% start.
Best of the rest
Mainz's three wins have put them at third in the league phase table at the midway point, but they trail Slovenia's Celje on goal difference while Samsunspor are top, a 3-0 win against Malta's Hamrun Spartans meaning the Turkish league phase debutants have yet to concede.
Alvaro Garcia hit an added-time winner as Rayo Vallecano battled back from 2-0 down against Lech Poznań. The Polish champions' half-time advantage was cancelled out by goals from Isi Palazón and Jorge De Frutos, Garcia deciding the game with the last meaningful action in Madrid.
After draws in their opening games, Finland's KuPS Kuopio celebrated their first-ever league phase win, 3-1 against Slovan Bratislava. It was also a good night for Ukrainian clubs, Shakhtar winning 2-0 against Breidablik before Dynamo Kyiv earned a 6-0 success against Zrinjski.