Real Madrid, the La Liga leaders, and PSG, the Ligue 1 leaders, lock horns in the second leg fixture of the UEFA Champions League on Wednesday.
The French side travel to the Santiago Bernabeu with a one-goal advantage, having outplayed the 13-time champions in the first leg to secure a 1-0 win with Kylian Mbappe scoring the winning goal in the fourth minute of injury time.
Real Madrid adopted a defensive approach in the first leg. However, Carlo Ancelotti has indicated that he will implement a high-press in the game and their 4-1 win over Real Sociedad saw that tactic in action on Sunday.
Real Madrid and PSG head into the second leg with contrasting fortunes
Real Madrid have made it three wins in a row since their 1-0 loss in the Champions League first leg while PSG have lost two of their three games. A piece of good news for the visiting side is that Madrid have progressed through to the next round of fixtures in the competition just once in the last 10 occasions when they lagged behind on aggregate after the first leg.
As the away goal rule is no longer applicable in the competition, a one-goal deficit is something Real Madrid can easily overcome, especially with the support of a sold-out Santiago Bernebau behind them.
As the semi-finalists from the previous edition look to make it to the next round of fixtures, we take a look at the five key battles which might help determine the outcome of the game.
#5 Luka Modric vs Marco Verratti
Real Madrid have built their attack from midfield with Toni Kroos and Luka Modric pulling the strings. Though PSG's buildup play has not been as refined this season, they can count upon the services of Marco Verratti to provide some steel in midfield.
Verratti was the most creative player in the first leg tie and generated six key passes throughout the game while also contributing at the back with three tackles and nine interceptions.
Luka Modric is the more experienced of the duo, with his midfielder partner Casemiro suspended for the game and Kroos a doubt, he will be the key midfielder for Madrid in the game and is expected to cross paths with the Italian.
The player coming out on top in this midfield battle will help dictate the run of play.
#4 Vinicius Junior vs PSG's full-backs
The PSG full-backs ran the show in the first half with their overlapping runs forcing Real Madrid to fall back and defend. Achraf Hakimi was particularly impressive against his former side and created three key passes for the Parisiens.
He was dribbled past just once in the game and came out on top against Vinicius Junior, Madrid's second-highest goalscorer this season. The Brazilian winger's creativity was dampened in the game as he had just one key pass to his name and managed just one successful dribble throughout the game. However, with Hakimi ruled out of the game, Vinicius Jr. could have a major impact.
Ancelotti won't have the defensive-minded left-back Ferland Mendy available for this game and as a result, will focus on pushing high up against the visitors, which could work in Vinicius' favor.
#3 Thibaut Courtois vs Lionel Messi
The second leg will provide Lionel Messi, the all-time top scorer in the round of 16 fixtures, an opportunity to redeem himself after failing to convert from the spot in the first leg. Thibaut Courtois came out on top with a strong left-handed save and kept his side in the game, though PSG scored an injury-time winner.
Courtois was impressive throughout the game and made eight saves. Messi, on the other hand, had four key passes to his name and recorded just one more shot apart from his penalty on target in the game.
The two players have a long-standing rivalry from Messi's time at Barcelona and Courtois' spells with Atletico Madrid and Chelsea.
#2 David Alaba vs Kylian Mbappe
Kylian Mbappe's involvement in the game is doubtful but he is so crucial to PSG at the moment that even if he is partially fit, he will be given the nod to start here.
The player has been linked heavily with Los Blancos and having scored the winning goal in the first leg, will be keen to repeat the feat. The PSG superstar had four shots on target in the first leg and even a cameo could be enough to make a difference here.
The task of neutralizing his threat will fall to David Alaba, a converted center-back who has excelled in that role. He led Real Madrid in terms of interceptions in the first leg (4) but seemed to struggle against Mbappe's sprints.
His experience will come in handy in what is expected to be a high-intensity game.
#1 Karim Benzema vs Marquinhos
With the hosts trailing by one goal in the game, Karim Benzema will have the opportunity to become the ultimate big-game player for Real Madrid in this second leg-tie.
While no player has been as influential for the club in the last four seasons. If he can replicate his league form against the visitors, he will finally emerge completely from Cristiano Ronaldo's shadow, who was often Real Madrid's match-winner in the knockout stages of the competition.
He has three goals and three assists in his last three league games, and so is the man in form in this game. He will face Marquinhos in the PSG box, who emerged as the better player in the first leg, denying the Frenchman an opportunity to record even a single shot on target.
The Brazilian defender did not miss out on a single minute of playing time in the Champions League this season. The PSG captain made as many as 10 recoveries in the first leg and alongside Presnel Kimpembe forms a physical, no-nonsense defensive partnership.