Messi set a record of 86 goals scored in a calendar year when he netted his second of the night in a La Liga game at Real Betis on Sunday, beating Gerd Müller's record of 85 goals in 1972.
The 25-year-old World Player of the Year award winner earlier equalled the record when he picked up the ball in a central position in the 16th minute and left the Betis defence standing, before sending an angled shot across goal into the bottom right corner.
Andrés Iniesta's clever back-heel set the Argentine up to score again nine minutes later with a sweeping shot that flew into the same corner of the goal.
Favourite to secure a fourth straight World Player of the Year award when the winner is announced next month, Messi has netted 74 times for Barca and 12 for Argentina in 2012 – beating Mueller's total for Bayern Munich and Germany in 1972.
Saturday's double took his tally in 15 La Liga outings this season to 23. – Reuters