(CNN) -- The message will have been heard loud and clear across Europe.
Bayern Munich, themselves on the end of a thrashing in the European Champions League semifinals last year, dished out one of its own on Tuesday.
The German champions, led by former Barcelona coach Pep Guardiola, raced into a five-goal lead over Italian side AS Roma in their group stages clash, with just 36 minutes on the clock.
It was a devastating display of attacking football that left the thousands of fervent fans gathered in Rome's Olympic Stadium shell shocked.
Except, of course, for those 5,000 supporters who had made the trip from Germany.
Guardiola is aiming for a hat-trick of Champions League triumphs after securing two during his four-year spell at the Spanish giants.
And if it carries on like this, Bayern will prove a tough nut to crack in the competition's latter stages.
The rout began on eight minutes, Dutch international Arjen Robben cutting inside former Chelsea defender Ashley Cole to bend a shot into the far corner.
Mario Gotze, whose winning goal sealed a World Cup triumph for Germany in Brazil, made it two after swapping passes with international teammate Thomas Muller.
Poland striker Robert Lewandowski made it 3-0 with a fine header from Juan Bernat's cross before Robben grabbed another, similar to his opener.
When Kostas Manolas was adjudged to have handled inside his own area, Muller stroked home the penalty to make it 5-0 in front of a stunned stadium.
Things did improve for Roma in the second half as Ivory Coast midfielder Gervinho got them on the scoresheet with a close range header, but it was only a brief respite.
Substitute Franck Ribery made it six, clipping the ball into the net after a precise through ball from Robben, before another sub -- Xherdan Shaqiri -- made it seven from close range.
It brought back painful memories for Roma of another seven-goal mauling, when it lost by the same scoreline to English side Manchester United back in 2007.
Bayern's third win from three outings saw it take firm control of Group E, with Roma second on four points.
Roma boss Rudy Garcia said: "We collapsed tactically and in terms of our aggressiveness. We let them play and they're too good for that. I was the first to make mistakes; it's not the players' fault."
Incredibly, Bayern's 45 minute heroics were bettered by Ukrainian side Shakhtar Donetsk, who raced into a 6-0 lead over BATE Borisov in Belarus at halftime to set a new Champions League record.
Shakhtar went on to win 7-0, Brazilian striker Luiz Adriano becoming only the second player to score five goals in a Champions League game, after Barcelona's Lionel Messi.
Those 15 goals across two matches helped bump Tuesday's tally to 40 across the eight games, a new record for the continent's most lucrative club competition.
News of Bayern's triumph will have provided succor for Manchester City, who were stunned by a late CSKA Moscow equalizer in Group E's other encounter, in Russia.
For the second time in a month its 18,600 capacity Arena Khimki was closed to fans after sanctions from European soccer's governing body relating to incidents of racism.
A controversial late penalty from Bebars Natcho canceled out goals from Sergio Aguero and James Milner meaning the star-studded Premier League holders now face an uphill task to qualify from its group.
The match was played out in sub zero temperatures and in front of just a handful of spectators after UEFA decreed CSKA's stadium must be closed to fans for its next three European games.
UEFA charged the club with racism for the third time in a year after troubled flared among its fans during CSKA's defeat to AS Roma in September.
The first came almost a year ago, when City's Ivorian midfielder Yaya Toure was subject to racist chanting from the stands.
Toure reacted furiously saying at some point UEFA had to ban a club "for a couple of years." CSKA hit back, saying the incident had been "very exaggerated."
There were no such flashpoints on Tuesday, given only a clutch of people were present to witness another poor European performance from City.
It had eased into a two-goal lead inside 38 first half minutes as it looked to register a first win in this season's competition.
A ball over the top from David Silva put Edin Dzeko in on goal and he unselfishly squared for Argentina striker Aguero to tap into an empty net. Less than 10 minutes later, Aguero's shot from inside the box fell perfectly for England international Milner to slide in and convert.
But as the match wore on City retreated, and after Ivory Coast international Seydou Doumbia had polished off a Ahmed Musa cross, he enticed Aleksandar Kolarov into a clumsy tackle, allowing Natcho to tuck home the penalty.
When asked how City had let its lead slip, manager Manuel Pellegrini told Sky Sports: "Because football is 95 minutes, we have scored two goals and had clear chances to score more but we didn't.
"I don't want to talk about the referee. We have nine more points to play and I am confident we will qualify."
Elsewhere, Lionel Messi moved within two goals of Raul's all-time Champions League scoring record with Barcelona's second goal in its 3-1 win over Dutch side Ajax.
Neyamr scored the opening goal before the Argentina struck his 69th Champions League goal, Sandro Ramírez adding a late third.
English Premier League leaders Chelsea thrashed NK Maribor of Slovenia 6-0 at Stamford Bridge, Didier Droga scoring his first goal for the club since rejoining prior to the start of the season. Eden Hazard netted twice.
An 87th minute strike from Uruguay forward Edinson Cavani helped French champions Paris Saint-Germain to a 1-0 victory over Apoel Nicosia in Cyprus.
A goal in the dying seconds from Eric Choupo-Moting sealed a 4-3 success for German club Schalke in a epic encounter with Portuguese side Sporting Lisbon.
But there was better news for Portugal as Porto registered a 2-1 victory over Spanish outfit Athletic Bilbao, courtesy of Ricardo Quaresma's winner.