Liverpool, Barcelona at the Pinnacle of the Best Champions League Comebacks Ever

Following Roma's dramatic comeback win over Barcelona, we ranked the best comebacks in Champions League history.

Roma pulled off one of the biggest upsets in UEFA Champions League history on Tuesday, rallying from a 4–1 deficit against Barcelona to score three at home and reach the semifinals on away goals. With the win in Italy, Roma became only the third Champions League team to erase a three or more goal hole after the first leg match.

As surprised as fans were on Tuesday, many know first-hand the incredible moments the Champions League has offered. Here are the five best comebacks in the competition's history. 

5. Monaco vs. Real Madrid, 2003–04, Quarterfinal

First leg result: Real Madrid 4–2 Monaco

Second leg result: Monaco 3–1 Real Madrid; Monaco advance on away goals

Spanish giants Real Madrid were just two years removed from a Champions League title and were in the semifinals the year before. In the quarterfinals, Madrid appeared to have a comfortable road to advance after jumping out to an easy 4–2 victory in the first leg behind goals from Zinedine Zidane, Luis Figo and Ronaldo. After Raul opened the second leg with a goal to make it 5–2 on aggregate, Monaco's hopes looked slim. 

But, Ludovic Giuly's low volley gave Monaco hope just before halftime and Fernando Morientes, on loan from Real Madrid, headed one home to make it 2–1 in favor of the home team. Giuly would strike again late and Monaco shocked the football world, advancing to the semifinals on away goals.

4. AS Roma vs. Barcelona, 2017–18, Quarterfinal

First leg result: Barcelona 4–1 Roma

Second leg result: Roma 3–0 Barcelona; Roma advance on away goals

Barcelona entered the second leg of their quarterfinal clash with Roma in a comfortable position. The Catalans had not lost a match in domestic or Champions League play all season and had not tasted defeat in 18 straight matches, including a 4–1 thrashing of Roma in the first leg of the competition at Camp Nou.

But Ernesto Valverde's side came out flat-footed, allowing a sixth minute goal to Edin Dzeko on a brilliant Daniele De Rossi long pass. De Rossi doubled Roma's lead shortly after half-time from the penalty spot and defender Kostas Manolas finished a beautiful header past Marc-Andre ter Stegen late in the game to dramatically propel Roma to the semifinals.

[youtube:https://www.youtube.com/watch?v=TC2wi9zlpKY]

3. Deportivo La Coruna vs. AC Milan, 2003–04, Quarterfinal

First leg result: AC Milan 4–1 Deportivo

Second leg result: Deportivo 4–0 AC Milan; Deportivo advance 5–4 on aggregate

Milan's team in 2004 was loaded with the world's best stars including Kaka, Andrea Pirlo, Paolo Maldini, Cafu and Andriy Shevchenko. A 4-1 loss in the first leg surely spelled defeat for Spanish club Deportivo La Coruna. But, as Deportivo coach Javier Irureta said before the second leg in Spain, "Miracles often happen, things you might not rationally expect."

Away from home, the defending champion and tournament favorite Milan were erratic early on, eventually succumbing to Deportivo's immense pressure in the form of an early Walter Pandiani goal. As the Riazor crowd bellowed, a Juan Carlos Valeron header and a fierce drive from Albert Luque about a minute from halftime erased Milan's first leg lead and would send Deportivo through. But Irureta's side wasn't satisfied yet, as they added one more for good measure on a brilliant volley from Fran to give the Galicians an astonishing quarterfinal victory.

2. Barcelona vs. PSG, 2016–17, Round of 16

First leg result: PSG 4–0 Barcelona

Second leg result: Barcelona 6–1 PSG; Barcelona advance 6–5 on aggregate

No team had ever rebounded from a four goal deficit in the Champions League until Barcelona shocked Paris and the world last season. The first leg in France produced disastrous results for Luis Enrique's side as Paris Saint-Germain handled business, winning 4-0 behind goals from Angel Di Maria and Julian Draxler.

Coming into the second leg, Barcelona failed to secure a crucial away goal and needed to put at least five past PSG to advance to the quarterfinals. A third-minute Luis Suarez header started the scoring for Barca, who then scored two more times within the first 50 minutes to put the pressure on the French side. PSG responded with a spectacular volley from Edinson Cavani, surely spelling doom for Barcelona. Chasing three more goals in the late stages of the game, Neymar curled a free kick past Kurzawa and just two minutes later converted a penalty to make it 5-5 on aggregate. But Barcelona still needed another miracle to counteract PSG's away goal. In the 95th minute, Sergi Roberto incredibly struck the game winning goal in the final seconds to complete one of the most incredible games in Champions League history.

1. Liverpool vs. AC Milan, 2004–05, Champions League Final

Result: Liverpool 3 - AC Milan 3; Liverpool win on penalties (3–2)

In the only one-leg match on the list, Liverpool overcame a three-goal deficit against mighty AC Milan to win the Champions League Final on penalties. On a clear night in Istanbul, Milan quickly took the lead on a brilliant volley from captain Paolo Maldini off a cross from Andrea Pirlo. Striker Hernán Crespo added two more goals before half-time to make it 3-0, creating a seemingly impossible task for Liverpool.

But Steven Gerrard gave Liverpool hope with a header into the right corner and Vladimir Smicer added another just two minutes later. Milan's lead would officially be erased in the 61st minute as Xabi Alonso followed up his missed penalty by rocketing a shot into the top of the netting. The score stayed level throughout regulation and extra time and the match headed to penalties, where Liverpool emerged 3-2 to win their fifth European Cup.