Muller recked up his record-breaking tally in just 60 matches for Bayern Munich and West Germany in 1972, while the Brazil icon, Pele, had previously sat in second place for most goals in a single year with his haul of 75 back in 1958. But then Messi nonchalantly swept past both of them in 2012.
Here, Goal takes a comprehensive look at how and when all of his goals occurred.
1 + 2 - January 4. vs Osasuna (h). Copa del Rey. (4-0). Started the year with a bang despite initially being confined to the bench with flu for this game. Scored twice in the second half after being introduced on the hour mark, the first a header and the second a wicked curling strike.
3 + 4 - January 15. vs Real Betis (h). Primera Division. (4-2). After showing off his Ballon d'Or award to the Camp Nou crowd ahead of kick-off the diminutive Argentine lived up to the hype by finishing a fine team move in the first half and then adding a penalty late on.
5, 6 + 7 - January 22. vs Malaga (a). Primera Division (4-1). Notched his first hat-trick of 2012 courtesy of a precise header and two magical solo efforts in the second half.
8 - February 4. vs Real Sociedad (h). Primera Division. (2-1). Sealed all three points for his side with a well-taken volley in the 72nd minute.
9 - February 14. vs Bayer Leverkusen (a). Champions League. (3-1). Scored Barcelona's final goal against their German opposition, following a nervy encounter at the BayArena.
10, 11, 12 + 13 - February 19. vs Valencia (h). Primera Division. (5-1). Inspired his team to victory with four goals in his 200th game for the club.
14 - February 26. vs Atletico Madrid (a). Primera Division. (2-1). Secured a hard-fought win for Barcelona with a stunning free kick from 25 yards in the 81st minute.
15, 16 + 17 - February 29. vs Switzerland (a). International Friendly. (3-1). Stole the show in Bern with a fine hat-trick that guided Argentina to victory.
18, 19, 20, 21 + 22 - March 7. vs Bayer Leverkusen (h). Champions League. (7-1). Made history by becoming the first player ever to score five times in a single Champions League match, as Barcelona ran riot at Camp Nou.
When Messi attacks
|44||The Argentine's 86 goals have all come in just 44 of the 66 matches he has played in during 2012|
|16||In just 16 of those 43 games did Messi score a single goal|
|19||In 19 of them he scored twice|
|6||While in six of those fixtures he netted three times|
|13||Number of goals Messi scored in March|
|6||Number of goals scored against both Malaga and Bayer Leverkusen in 2012|
23 + 24 - March 11. vs Racing Santander (a). Primera Division. (2-0). Bagged his 49th and 50th goals of the 2011-12 season with a close range finish and a confident penalty in the second half.
25 - March 17. vs Sevilla (a). Primera Division. (2-0). Scored twice at the Ramon Sanchez Pizjuan as Barcelona cruised to a comfortable win.
26, 27 + 28 - March 20. vs Granada (h). Primera Division. (5-3). Netted his third hat-trick of 2012 in an eight-goal Liga thriller at Camp Nou.
29 - March 24. vs Mallorca (a). Primera Division. (2-0). Helped Pep Guardiola's side win their 50th competitive match of the season by opening the scoring with a curling free kick in the 25th minute.
30 - March 31. vs Athletic Bilbao (h). Primera Division. (2-0). Scored a second-half penalty as the Catalan giants brushed aside their tired opponents that had played in the Europa League just 48 hours earlier.
31 + 32 - April 3. vs Milan (h). Champions League. (3-1). Broke the record for most goals in a single Champions League season (14) with two penalties, as Barcelona advanced to the semi-finals.
33 + 34 - April 7. vs Real Zaragoza (a). Primera Division. (4-1). Reached the 60-goal mark for the 2011-12 season as his side laboured to victory at La Romareda.
35 - April 10. vs Getafe (h). Primera Division. (4-0). Smashed a devastating finish past Miguel Moya just before the interval as Barcelona romped to victory at Camp Nou.
36 + 37 - April 14. vs Levante (a). Primera Division. (2-1). Scored twice to overturn Levante's first-half lead and seal all three points for his side.
38 + 39 - April 29. vs Rayo Vallecano (a). Primera Division. (7-0). Ensured a harrowing week for the club ended on a high following their Champions League exit at the hands of Chelsea by scoring two goals from close range as Barcelona hit seven past Rayo.
40, 41 + 42 - May 2. vs Malaga (h). Primera Division. (4-1). Further stamped his name in the history books with three goals that took him to 68 for the season, surpassing the previous European record tally set by Gerd Muller in 1972-73.
43, 44, 45 + 46 - May 5. vs Espanyol (h). Primera Division. (4-0). Scored all four goals for the Blaugrana as they hammered their local rivals in La Liga.
47- May 25. vs Athletic Bilbao (a). Copa del Rey Final. (3-0). Helped his side win the Copa del Rey, netting the second of their three goals with a sumptuous effort with the outside of his left foot.
48 - June 3. vs Ecuador (h). World Cup Qualifier. (4-0). Curled a shot past Alexander Dominguez on the half hour mark to make it 3-0 as Albiceleste marched to a comfortable victory.
49, 50 + 51 - June 9. vs Brazil (h). International Friendly. (4-3). Put in a phenomenal performance in New Jersey as Argentina took on their bitter rivals in a showpiece friendly, scoring a wonderful hat-trick to lead his team to victory.
52 - August 15. vs Germany (a). International Friendly. (3-1). Swept home Argentina's second goal from the edge of the box, as they dominated their friendly against Joachim Low's team.
53 + 54 - August 19. vs Real Sociedad (h). Primera Division. (5-1). Got Tito Vilanova's reign as Barcelona coach off to a flyer by finding the net twice as the Catalan giants hit five past Sociedad.
55 - August 23. vs Real Madrid (h). Supercopa. (3-2). Helped Barca win the first leg of the Supercopa by sending Iker Casillas the wrong way with a second-half penalty.
56 + 57 - August 26. vs Osasuna (a). Primera Division. (2-1). Inspired his team to victory with a late double after Joseba Llorente had given the Pamplona-based side a 1-0 first-half lead.
58 - August 29. vs Real Madrid (a). Supercopa. (1-2). Fired a fantastic free kick past Iker Casillas on the brink of half-time to keep Barcelona in the game and just a goal behind, but could do nothing in the second half as Madrid held out for the win.
59 - September 8. vs Paraguay (h). World Cup Qualifier. (3-1). Scored another glorious set piece in a confident showing from Alejandro Sabella's side.
60 + 61 - September 15. vs Getafe (a). Primera Division. (4-1). Came off the bench to bag two goals for Barcelona as they maintained their 100% start to the Liga season under Vilanova.
62 + 63 - September 19. vs Spartak Moscow (h). Champions League. (3-2). Rescued his team with two more late goals, after their Russian opponents had gone 2-1 up in the 59th minute through Romulo.
64 + 65 - October 7. vs Real Madrid (h). Primera Division. (2-2). Locked horns with Cristiano Ronaldo to much acclaim as each player scored two fine goals that meant the pulsating game ended in a draw.
66 + 67 - October 13. vs Uruguay (h). World Cup Qualifier. (3-0). Two goals from Messi helped Sabella's men secure a comfortable win over their Rioplatense neighbours, with the Barcelona forward's second a joy to behold, as he rattled a free kick under Uruguay's jumping wall and into the bottom corner.
68 - October 17. vs Chile (a). World Cup Qualifier. (2-1). Scored the first goal of the game in the 28th minute as Argentina edged past the Roja.
69, 70 + 71 - October 20. vs Deportivo (a). Primera Division. (5-4). Helped make it 12 games unbeaten in La Liga for Barcelona with a well-taken hat-trick, as the Riazor played host to a nine-goal thriller, with six of those being scored before half-time.
72 + 73 - October 27. vs Rayo Vallecano (a). Primera Division. (5-0). Notched his 300th senior goal for club and country with a thumping strike three minutes into the second half, before adding a second moments before the end.
74 - November 7. vs Celtic (a). Champions League. (1-2). Scored his side's only goal as they fell victim to a shock 2-1 defeat against Neil Lennon's team.
75 + 76 - November 11. vs Mallorca (a). Primera Division. (4-2). Reached another milestone with two strikes in this match, as he surpassed Pele's mark of 75 goals in a calendar year.
77 + 78 - November 17. vs Zaragoza (h). Primera Division. (3-1). Got himself on the scoresheet twice in a game devoid of many clearcut chances, as Barcelona made it 11 wins out of 12 in La Liga this campaign.
79 + 80 - November 20. vs Spartak Moscow (a). Champions League. (3-0). Moved to within five of Gerd Muler's 85-goal record with two goals in Moscow, while also equalling Ruud van Nistelrooy's tally of 56 Champions League strikes.
81 + 82 - November 25. vs Levante (a). Primera Division. (4-0). Netted his 18th double of 2012 with a nonchalant lob over Gustavo Munua, and a close-range finish after some superb build-up play from Andres Iniesta.
83 + 84 - December 1. vs Athletic Bilbao (h). Primera Division. (5-1). Helped Barcelona make the best-ever start in Liga history by scoring twice as they romped past Bilbao at Camp Nou, while on a personal level he moved to within one of Muller's astonishing record.
85 + 86 - December 9. vs Betis (a). Primera Division (2-1). Messi made a quick recovery from a brusied knee sustained against Benfica four days earlier and opened the scoring with a diagonal run and angled drive back across Betis goalkeeper Adrian to draw level with the German great. The Argentine added a second with an opportunistic left-footed drive short of the half-hour mark after he was set up by Andres Iniesta. With three games still left for Barca in 2012, Leo had broken Muller's magical mark.
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