#3 UEFA Champions League final against Manchester United, 2009
An identical game to the fifth entry on our list, the 2009 Champions League final proved to be a very special one for both Lionel Messi and Barcelona. The 26-times Spanish champions were fresh off winning a domestic double and had their eyes on the elusive European title.
In an evenly poised match against Manchester United, Samuel Eto'o opened the scoring for Barcelona in the 10th minute. However, Lionel Messi's 70th-minute header sealed the competition for the Blaugrana, creating history in the process.
His towering strike meant Barcelona became the first-ever Spanish side to win a continental treble. The Argentine number 10 commemorated the goal by kissing his fallen boot, a celebration that has gained iconic status since.
Pep Guardiola's men went on to secure another three trophies that season, a feat that had never been accomplished by any European team in the history of football until then.
The fabled 'sextuple' was recently replicated by Hansi Flick's rampant Bayern Munich in 2020.
#2 Supercopa de España against Real Madrid, 2012
The 2012 edition of the Supercopa de España, or more commonly known as the Spanish Super Cup, was played between arch-rivals Barcelona and Real Madrid over two games, home and away.
Even though the aggregate score amounted to four on each side, Los Blancos ran out victors on the pretext of away goals. However, the second leg witnessed a once-in-a-lifetime free-kick, scored by none other than Lionel Messi.
With Madrid leading the night by two goals, Barcelona was awarded a free kick in the final moments of the first half. The chances of bouncing back through this opportunity looked bleak as the spot was at least 35-40 yards away from the goal. Enter Lionel Messi.
The six-time European Golden Shoe awardee banged in a curler in the top-left corner of the goal, giving Iker Casillas no chance of saving that beauty.
However, that strike proved to be the last goal of the game, rendering Lionel Messi's efforts vain.
#1 Copa del Rey final against Athletic Bilbao, 2015
Arguably the best of his 748 strikes, Lionel Messi's astonishing solo effort against Athletic Bilbao in the 2015 Copa del Rey final can easily stand its ground among the greatest goals ever scored in the history of the game.
After receiving the ball from Dani Alves on the right flank of the opposition's half, Messi went on a rampage, dribbling past four Bilbao players as if they were cones on a training facility.
He then slotted the ball past Iago Herrerín at the near post to finish off a mind-numbing attack.
This wondrous strike broke the stalemate between Barcelona and the Basque club, with the score latched at nil-nil in 20 minutes of regulation time.
Lionel Messi found the net for the second time in the 74th minute to bring the tally up to 3-0 and seal the deal for the Catalan giants.
Barcelona subsequently won their 27th Copa del Rey title by a 3-1 scoreline, securing their second title of the season. Luis Enrique would later go onto lead the team to the second treble in the club's history.
Lionel Messi was honored with the Ballon d'Or at the end of the 2014-15 season, his fifth at the time, while his goal against Bilbao grabbed second place in that year's FIFA Puskás Award.
Honorable mention: Somewhat reminiscent of his aforementioned 2015 goal, Lionel Messi combined with Frenkie de Jong to produce a similar goal in 2021.
Poetically, the concerned game was the final of the Copa del Rey, where Barcelona decimated Athletic Bilbao 4-0, yet again.