It is often said that the Champions League only really gets properly started in the knockout stages.
With the group phase now known as the League Phase in the revamped competition out of the way, getting it right is vital and that is where the top players so often make the difference.
The Champions League has featured a round of 16 since the 2003/04 season and since then, there have been many memorable individual performances in the competition's first knockout round. Here, a look at some of the very best...
Thierry Henry (Arsenal vs Real Madrid, February 2006)
Arsenal reached the Champions League final in 2006 and Thierry Henry was the inspiration behind an impressive win over Real Madrid in the round of 16.
Henry received the ball in the centre circle in the first leg at the Santiago Bernabu and stormed through the Madrid back line before slotting past Iker Casillas. A clip of Henry nonchalantly seeing out time by the corner flag at the Bernabu has also recently resurfaced. He was a special talent. The Frenchman's moment of brilliance was the only goal of the night and also in the tie. A worthy winner.
Duan Tadi (Ajax vs Real Madrid, March 2019)
Beaten 2-1 in the first leg at home by Real Madrid despite a good performance on the night, few expected Ajax to advance to the Champions League quarter-finals in 2018/19.
But Erik ten Hag's side stunned Los Blancos in an incredible 4-1 win at the Santiago Bernabu, with Duan Tadi assisting the opening two goals and then scoring himself in an impressive individual and collective display in the Spanish capital.
Lionel Messi (Barcelona vs AC Milan, March 2013)
Barcelona were beaten 2-0 by AC Milan at the San Siro in the first leg of the teams' Champions League last-16 tie in February 2013, but overturned that deficit with a memorable comeback at Camp Nou three weeks later.
Lionel Messi was the inspiration, scoring Bara's first two goals with stunning strikes from outside the area in the first half to mastermind a special win. David Villa and Jordi Alba scored the others.
Cristiano Ronaldo (Real Madrid vs Schalke, February 2014)
Real Madrid's long wait for a 10th European Cup came to an end in 2014 with victory over city rivals Atltico Madrid in the final in Lisbon.
Los Blancos began the knockout stages with a stunning 6-1 win away to Schalke, with Karim Benzema, Gareth Bale and Cristiano Ronaldo all scoring twice. As well as his two goals, the Portuguese also assisted both of Benzema's efforts in a superb showing. In the second leg, Ronaldo netted two more in a 3-1 win to wrap up a 9-2 aggregate victory.
Serge Gnabry (Bayern Munich vs Chelsea, February 2020)
Serge Gnaby scored four as Bayern Munich thrashed Tottenham 7-2 in north London in the Champions League group stages in October 2019.
And the former Arsenal attacker impressed again on his next visit to London, netting twice as Bayern beat Chelsea 3-0 at Stamford Bridge in February. The Bavarians won the second leg 4-1 in Munich and went on to win the treble, with Gnabry scoring nine goals across 10 games in Europe.
Benni McCarthy (Porto vs Manchester United, February 2004)
Porto won the Champions League in 2004 and Jos Mourinho's side knocked out Manchester United in the last 16.
Benni McCarthy scored twice in a 2-1 win for the Portuguese side at the Estdio do Drag�o, converting with a super volley in the first half and then securing victory with a brilliant header in the second period. In the second leg at Old Trafford, the South African's free-kick led to Costinha's late equaliser, as Tim Howard could only parry and his effort and the tie turned in Porto's favour.
Sadio Man (Liverpool vs Bayern Munich, March 2019)
Sadio Man was a hugely important player for Liverpool at his best and the Senegalese attacker was on target twice as the Reds beat Bayern Munich 3-1 at the Allianz Arena in March 2019.
After a goalless draw in the first leg at Anfield, Man brought down a long pass from Virgil van Dijk in the area, wrong-footed goalkeeper Manuel Neuer and calmly fired into the net. He added another late in the game with a far-post header from a Mohamed Salah cross and Liverpool went on to win the trophy, beating Tottenham in the final.
Sylvain Wiltord (Lyon vs Werder Bremen, March 2005)
Sylvain Wiltord hit a hat-trick for Lyon as the French side thrashed Werder Bremen 7-2 in the Champions League last 16 in March 2005.
The former Arsenal striker scored Lyon's first, fourth and sixth goals in a huge win at the Stade Gerland as Paul Le Guen's side sealed a 10-2 aggregate victory.
Adriano (Inter vs Porto, March 2005)
Inter came up against defending European champions Porto in the last 16 of the Champions League in 2004/05.
After a 1-1 draw in Portugal, Adriano was the inspiration behind a 3-1 win for Inter at San Siro, scoring a brilliant hat-trick to send the Nerazzurri through to the last eight.
Pierre-Emerick Aubameyang (Borussia Dortmund vs Benfica, March 2017)
Borussia Dortmund thrashed Benfica 4-0 in the second leg of the teams' Champions League last-16 tie in March 2017 and Pierre-Emerick Aubameyang was the star of the show.
With Dortmund trailing 1-0 from the first match in Lisbon, Aubameyang levelled the tie with a header at the far post and after Christian Pulisic had made it 2-0 to BVB on the night, the Gabonese forward added two more in the second half to seal a 4-1 aggregate win for Thomas Tuchel's side.
Kylian Mbapp (Paris Saint-Germain vs Barcelona, February 2021)
With the Camp Nou empty due to Covid-19 restrictions, Kylian Mbapp scored a hat-trick as Paris Saint-Germain beat Barcelona 4-1 in the teams' Champions League last-16 first leg clash in February 2021.
Mbapp also scored a penalty in a 1-1 draw in the second match at the Parc des Princes as PSG advanced to the last eight with a 5-2 victory on aggregate.
Josip Ilii (Atalanta vs Valencia, March 2020)
Atalanta's 4-1 win over Valencia in February 2020 was played in front over 40,000 fans at San Siro, but the return took place at an empty Mestalla three weeks later due to Covid-19 restrictions.
The Italian side came out on top again as Josip Ilii scored all four goals, including two penalties, in a 4-3 win. The Slovenian attacker was also on target in the first match.
Karim Benzema (Real Madrid vs Paris Saint-Germain, March 2022)
Real Madrid's first Champions League win in the post-Cristiano Ronaldo era came in 2022 and in the absence of the Portuguese, Karim Benzema stepped up with a series of big goals.
Benzema hit a hat-trick in the final half an hour at the Santiago Bernabu as Madrid came back from 2-0 down in the tie to defeat Paris Saint-Germain 3-2 on aggregate. In the quarter-finals, the Frenchman hit another treble as Los Blancos beat Chelsea 3-1 at Stamford Bridge.
Mario Gmez (Bayern Munich vs Basel, March 2012)
Mario Gmez scored four goals as Bayern Munich thrashed Basel 7-0 at the Allianz Arena in the Champions League last 16 in March 2012.
Bayern overcame a 1-0 deficit with ease in the second match and Gmez scored the Bavarians' third, fourth, fifth and sixth goals in Munich, with three of those assisted by Franck Ribry.
Cristiano Ronaldo (Juventus vs Atltico Madrid, March 2019)
Cristiano Ronaldo's eighth Champions League hat-trick came in a last-16 tie between Juventus and Atltico Madrid in March 2019 and inspired a 3-2 aggregate win for the Bianconeri.
Following a 2-0 loss in Madrid, the Portuguese scored two trademark headers and converted a late penalty to seal an impressive comeback in Turin.
Neymar (Barcelona vs Paris Saint-Germain, March 2017)
No team in Champions League history had overturned a 4-0 first-leg deficit, but Barcelona became the first to achieve that with an incredible 6-1 win over Paris Saint-Germain at Camp Nou in March 2017.
Neymar was the architect of Bara's remarkable remontada, winning a penalty which Lionel Messi converted, scoring a late free-kick and another spot-kick before setting up Sergi Roberto to seal a dramatic and stunning victory deep in added time. Bara would end up losing to Juventus in the next round and PSG shocked the Catalan club by leaving for PSG in the summer.
Vincius Jnior (Real Madrid vs Liverpool, February 2023)
Real Madrid may not have won the Champions League in 2023, but Los Blancos produced a stunning comeback from 2-0 down to beat Liverpool 5-2 at Anfield in the round of 16.
Trailing to goals from Darwin Nez and Mohamed Salah, Madrid levelled the game at 2-2 thanks to a Vincius Jnior double and the Brazilian later assisted Karim Benzema for the Frenchman's second in a stunning win. After the game, Madrid coach Carlo Ancelotti said: "Vincius, right now, in my personal opinion, is the most decisive player in world football."
Erling Haaland (Manchester City vs RB Leipzig, March 2023)
Manchester City won the Champions League for the first time in 2023 and Erling Haaland was absolutely key as Pep Guardiola's side claimed a historic treble.
Haaland scored 12 goals in 11 games en route to the trophy, including five in a stunning 7-0 win over RB Leipzig in the last 16. And the Norwegian admitted he was disappointed to have been taken off in the 62nd minute by Guardiola, with no player having hit a double hat-trick in the Champions League.
Lionel Messi (Barcelona vs Bayer Leverkusen, March 2012)
Lionel Messi scored five goals for Barcelona in a 7-1 win over Bayer Leverkusen at Camp Nou in the teams' last-16 second leg match in March 2012.
After netting once in a 3-1 victory in the first match in Germany, the Argentine became the first player to score five in a Champions League match with an incredible performance in the return to seal an amazing 10-2 aggregate score.
