Liverpool lost its first Champions League game since raising the trophy in Madrid last May, while Lionel Messi made his first appearance for Barcelona this season.

Napoli beat the reigning champion Reds 2-0 on a late Dries Mertens penalty, while Barca was fortunate to finish scoreless at Borussia Dortmund.

Napoli scores twice late to beat Liverpool

Napoli broke the deadlock in the 82nd minute through Dries Mertens’ penalty, but not without a bit of controversy.

Liverpool fullback Andrew Robertson was judged to have brought down José Callejón in the box, but replays showed that while Robertson whiffed on his challenge, Callejón thrust himself forward in an attempt to draw a whistle.

He succeeded either way, and Mertens made no mistake (via Bleacher Report):

Fernando Llorente tagged on the second goal in stoppage time for Napoli, and Mexican international Hirving “Chucky” Lozano started and acquitted himself well. Liverpool looked dangerous as usual going forward, but the end product wasn’t quite there.

Fortunately for the Reds, they look to be clear co-favorites with Napoli in a group that also includes RB Salzburg and Genk, although Jesse Marsch’s Austrian champions were convincing in their own right.

Lionel Messi makes season debut as Barca draws

Barcelona’s glimpse of life without Lionel Messi has had its ups and downs thus far.

He returned to the Catalan side around the hour mark on Tuesday, replacing 16-year-old Ansu Fati, who has shown flashes of brilliance in his brief time with the senior team.

But goalkeeper Marc-André ter Stegen stole the spotlight from both.

Ter Stegen made four saves and swallowed up Dortmund chances all night. He preserved the draw by stopping Marco Reus’ penalty in the 56th minute:

Barcelona looked distressingly unimaginative and very easily could have lost, but it will gladly take a tough away point to start this Champions League campaign.

Group F, which also features Inter Milan, might well be the toughest collection of teams at this stage. So the suspense is just beginning.

Fortunately for Barcelona and fans across the world, Messi is back for it.

Inter Milan avoids embarrassment with late equalizer

At home vs. Slavia Prague figured to be the most straightforward fixture for Inter in the group stage. And they very nearly bungled it.

Nicolò Barella came to the rescue with a bounding volley off a crossbar deflection in stoppage time:

Romelu Lukaku would have set off celebrations at the San Siro if not for Ondřej Kolář’s quick reflexes shortly after:

Champions League scores

Napoli 2-0 Liverpool

Borussia Dortmund 0-0 Barcelona

Inter Milan 1-1 Slavia Prague

Lyon 1-1 Zenit St. Petersburg

Chelsea 0-1 Valencia

RB Salzburg 6-2 Genk

Ajax 3-0 Lille

Benfica 1-2 RB Leipzig

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