Messi hits 21st Barcelona hat-trick in nervy win
Jordi Alba and Cristian Tello got the other goals for Barca, who had Javier Mascherano sent-off on 48 minutes, while a Pizzi double, a Alex Bergantinos strike and an Alba own goal kept the home side in the game.
The win means Barca go three points clear of Atletico Madrid, who play on Sunday, at the top of La Liga.
Messi now has 11 league goals, two more than Cristiano Ronaldo who earlier scored for Real Madrid in a 2-0 win over Celta Vigo that kept Madrid right points behind the Catalan side.
Alba put Barca ahead on the north-west coast after only two minutes, bursting into the area to meet a Cesc Fabregas pass and finish well and, five minutes later, the lead was doubled.
Messi dinked the ball out wide for Tello who moved from right to left and then back to his right foot before hitting an unstoppable shot past Dani Aranzubia in the Deportivo goal.
Barca's third 10 minutes later was the pick of the evening.
Mascherano played a forward pass from the halfway line that Fabregas controlled and back-heeled into the path of Messi who powerfully struck a left-footed shot into the top right hand corner.
Deportivo had been undone by Barca's clever passing play in less than 20 minutes but came back quickly to earn a dubious penalty when Mascherano fouled Riki on 25 minutes that Pizzi converted.
Then, on 37 minutes, Bergantinos hit a shot from the edge of the area that Victor Valdes seemed to have covered but suddenly fumbled over the line to make it 2-3.
Barca appeared stunned only for Fabregas to then conjour up another brilliant pass for Messi to finish, this time with his right foot, to regain a two-goal cushion at the break.
However, Depor were not finished and within two minutes of the re-start Pizzi had smashed in his second from a free-kick.
Three minutes later Mascherano was given his marching orders for a second questionable clash with Riki who went down holding his face after the two tussled for a ball.
Messi then hit the bar from a free-kick and the action was non-stop as the home side tried to find an unlikely equaliser.
It was Messi who struck again for his third, wrestling to get the ball away from Spain's World Cup winning defender Carlos Marchena before running at the remaining defenders before hitting a shot home to make it 5-3.
Again Depor hit back straightaway as Alba turned a ball into his own goal as he tried to stop Pizzi from hitting his own hat-trick.
Goalkeeper Aranzubia came forward for a last-minute corner but it was not to be for a battling Deportivo and Barca took the points in a breathtaking match.
Earlier Gonzalo Higuain and Ronaldo hit a goal apiece as Real Madrid eased past their unambitious opponents.
Higuain put Madrid ahead in the 12th minute when he powered down the left wing and hit what looked like a cross that curled into the far corner.
Madrid had further chances but needed the help of the referee more than an hour later when he awarded what seemed a controversial penalty after Mesut Ozil went down under a challenge from Gustavo Cabral on 68 minutes.
Ronaldo made no mistake from the spot to make it nine league goals for the season and give Madrid the points.
Valencia came from behind on two occasions to beat Athletic Bilbao 3-2.
Their former striker Aritz Aduriz twice put the visitors ahead, but a fighting performance, including a penalty from Roberto Soldado and a goal apiece from Tino Costa and Nelson Valdez in the last two minutes, gave the home side some respite from growing supporter displeasure after previously only winning two of their first seven games.
Malaga came from behind to beat Valladolid with a hard earned 2-1 home victory to stay in third position
Supreme Court on Friday pronounced that Sunil Gavaskar will replace N Srinivasan to take up the post of interim president of the BCCI. The S... More Supreme Court on Friday pronounced that Sunil Gavaskar will replace N Srinivasan to take up the post of interim president of the BCCI. The Supreme Court gave three interim orders to the BCCI, that is, Rajasthan Royals and Chennai Super Kings will not take part in IPL 7 tournament, Gavaskar replacing Srinivasan, and all India Cements employess be removed from BCCI.
Date 27-03-14, Duration 1:52, Views 700