That was exactly what we love about the UEFA Champions League.
European football's premier club competition returned Tuesday, and little about the day's eight matches disappointed.
Real Madrid and Manchester City played out the match of the day—maybe even the match of the group stage—but they weren't the only teams producing drama.
Read on for all the details from the exciting first half of the group stage's first matchday.
Porto, the champions of Portugal's Primeira Liga, scored near the end of each half to start their Champions League campaign with a road win in Group A.
Lucho Gonzalez (pictured) scored Porto's first goal in a crowded box in the 41st minute to give the visitors a 1-0 halftime lead over Croatian champions Dinamo Zagreb.
Steven Defour made it 2-0 in the second minute of second-half stoppage time.
Up next: Porto host Group A co-leaders Paris Saint-Germain on Oct. 3, while Zagreb travel to Dynamo Kiev.
Big-spending Paris Saint-Germain ripped Dynamo Kiev with three first-half goals before eventually winning, 4-1, at the Parc des Princes.
PSG invested heavily in the squad this summer, bringing in forward Zlatan Ibrahimovic (pictured, front) and defender Thiago Silva, among other big names. Those two were responsible for PSG's first two goals Tuesday, with Ibra breaking the deadlock with a 19th-minute penalty before Silva doubled the lead 10 minutes later.
Alex turned in a corner for a 3-0 lead in the 32nd minute. PSG cruised to the Group A win in the second half.
Miguel Veloso grabbed a consolation goal for Dynamo Kiev in the 87th minute, but Javier Pastore restored PSG's three-goal margin in the first minute of second-half stoppage time with PSG's fourth goal.
Up next: PSG travel to Porto on Oct. 3, while Kiev host Dinamo Zagreb.
Arsenal reversed an early deficit against newcomers Montpellier and started the new Champions League campaign with an away win in Group B.
Younes Belhanda, who troubled Arsenal's defense throughout the match, won a penalty and converted it with a Panenka kick in the ninth minute. It was the first-ever Champions League goal for Montpellier, who were making their debut appearance in Europe's elite club competition.
Lukas Podolski equalized for Arsenal in the 16th minute after a flowing move involving Santi Cazorla and Olivier Giroud, who transferred from Montpellier to Arsenal over the summer. It was Podolski's first Champions League goal since 2009 with Bayern Munich against Sporting Lisbon.
Gervinho scored the winner just two minutes later. Montpellier threatened repeatedly in the second half, and both Belhanda and Remy Cabella missed good chances inside the Arsenal box.
10 - Montpellier attempted 10 more shots than Arsenal tonight. Novice.— Opta (@OptaJean) September 18, 2012
Bonus Twitter stat:
Arsenal extend their unbeaten streak in European away matches against French clubs - 10 matches - 6 wins 4 -draws.— Infostrada Sports (@InfostradaLive) September 18, 2012
Up next: Arsenal, who finished third in the English Premier League last season, host Greek champions Olympiakos on Oct. 3. The same teams met in the group stage last season, with each winning at home.
Montpellier travel to Germany to face Schalke 04 the same night.
Klaas-Jan Huntelaar scored the second-half winner, as Schalke recorded a Group B victory away from home against Greek champions Olympiakos.
Schalke, the third-placed team in Germany's Bundesliga last season, went ahead in the 41st minute through captain and defender Benedikt Howedes.
Djamel Abdoun equalized for Olympiakos in the 58th minute, but Huntelaar restored Schalke's lead only one minute later with a shot that hit off the left-hand post before settling into the side netting on the right.
Huntelaar missed a penalty moments later, but Schalke held the lead, with Rafik Djebbour shooting over the bar from six yards in stoppage time.
#Schalke had 54% of the ball in their 2-1 win over Olympiacos. The Blues out-shot hosts 18-3, but only hit the target four times.— DW - Sports (@dw_sports) September 18, 2012
Up next: Olympiakos travel to Arsenal on Oct. 3, while Schalke host Montpellier.
AC Milan's slow start to the season continued with a disappointing home draw against Belgian champions Anderlecht in a Group C match at the San Siro.
Milan, the runners-up in Italy's Serie A last season, lost, 1-0, to Atalanta in league play over the weekend. The Rossoneri struggled again, with only four of their 20 shots hitting the target.
Anderlecht had a late chance to win the match, but Dieudonne Mbokani hit his shot over the bar.
AC Milan have scored ZERO goals in all three of their home matches this season in all competitions.— Infostrada Sports (@InfostradaLive) September 18, 2012
Up next: Milan travel east to face Russian champions Zenit St. Petersburg on Oct. 3, while Anderlecht host early Group C leaders Malaga.
Malaga impressed in their Champions League debut, as Isco scored twice in a resounding 3-0 victory at home over Russian champions Zenit St. Petersburg.
With the win, Malaga top Group C with three points. Manuel Pellegrini's team finished fourth in Spain's La Liga last season, but endured a tough summer due to the club's ongoing financial problems.
Isco, a 20-year-old attacking midfielder, scored Malaga's first-ever Champions League goal in the third minute. Javier Saviola doubled the lead 10 minutes later and Isco made it 3-0 in the 76th minute.
10 - Málaga are the tenth Spanish team to win a game in the Champions League in the XXI century. Growth— OptaJose (@OptaJose) September 18, 2012
Bonus Twitter stat:
5 - Isco is the fifth Spanish player to score one brace in the CL in the last two seasons (Callejón, Pedro, Tello and Torres). Promise— OptaJose (@OptaJose) September 18, 2012
Up next: Zenit host AC Milan on Oct. 3, while Malaga travel to Anderlecht.
Mats Hummels missed a second-half penalty before Robert Lewandowski (pictured) scored a late winner, as two-time defending German champions Borussia Dortmund defeated Ajax, 1-0, at home in Group D, this season's "Group of Death."
Dortmund exited the Champions League at the group stage last season, but started the current campaign well thanks to Lewandowski's 87th-minute strike. The goal can be viewed here.
Ajax, the two-time defending Dutch champions, conceded a penalty in the 58th minute. Hummels, a German international defender, struck his shot poorly and Kenneth Vermeer saved easily.
Up next: Ajax host Spanish champions Real Madrid on Oct. 3, while Dortmund travel to English Champions Manchester City.
Real Madrid overcame a late deficit—prompting manager Jose Mourinho to slide on the field in his suit—to defeat Manchester City, 3-2, in the day's most exciting match.
Manchester City, the reigning English Premier League champions, took the lead in the 68th minute through Edin Dzeko, who was set up by Yaya Toure's powerful run through midfield.
Real, the reigning Spanish champions, equalized eight minutes later on Marcelo's deflected shot.
City scored what seemed to be the winner in the 85th minute with defender Aleksandar Kolarov's free kick, which was deflected into the net by Real's Xabi Alonso. But Real responded with two goals in the final three minutes to produce a stirring comeback.
Karim Benzema evened the score with a low shot two minutes later, and Portuguese superstar Cristiano Ronaldo scored the winner with a dipping shot from the edge of the area. The shot appeared to confuse City defender Vincent Kompany, who let the ball fly over his head.
Ronaldo's winning goal can be viewed here.
Mourinho's sliding celebration can be viewed here. The Real manager's show of emotion came after his team's disappointing start to the season.
The victory came three days after Real Madrid suffered a 1-0 upset loss at Sevilla in La Liga play. The defending champions have already lost twice in the league this season and trail early leaders Barcelona by eight points.
39 - Cristiano Ronaldo has scored 39 goals in the Champions League, the same as Didier Drogba. Giants— OptaJose (@OptaJose) September 18, 2012
Bonus Twitter stat:
50 - Cristiano Ronaldo didn't misplace a single pass tonight vs Manchester City, completing 50 out of 50. Master #RealCity— OptaPaolo (@OptaPaolo) September 18, 2012
Up next: Manchester City host Borussia Dortmund on Oct. 3, while Real Madrid travel to Ajax.
Eight more matches are scheduled for Wednesday.
Here they are, listed by group. All matches are scheduled to start at 2:45 p.m. ET.
Chelsea vs. Juventus
Shakhtar Donetsk vs. FC Nordsjaelland
Bayern Munich vs. Valencia
Lille vs. BATE Borisov
Barcelona vs. Spartak Moscow
Celtic vs. Benfica
Braga vs. CFR Cluj-Napoca
Manchester United vs. Galatasaray