Barcelona's forward Lionel Messi celebrates after scoring against Zaragoza during their Spanish League football match Barcelona against Zaragoza at Romareda stadium in Zaragoza. Messi made it four goals in four days scoring a brace as Barcelona won 2-0 at 10-man Real Zaragoza on Saturday to replace arch rivals Real Madrid at the top of the Spanish first division. [Xinhua/AFP Photo]

Leo Messi scored two goals as Barcelona cruised to a comfortable 2-0 win away to bottom of the table Zaragoza.

Messi had scored twice in the midweek Champions league win over Copenhagen and was again match-winner as the Catalans brushed past a defensive Zaragoza that played almost all of the second half with a player less following Ponzio' s sending off.

Barcelona were without midfielder Xavi Hernandez who was still suffering from an Achilles tendon problem.

Meanwhile Zaragoza recovered Jarosik in defense following his suspension last week, but lost Pinter, who was sent off in the 2-1 defeat away to Athletic Club Bilbao.

That result left Jose Aurelio Gay' s team bottom of the table and the coach in danger of losing his job and Gay responded by packing his defense and looking to close Barca out.

The visitors struggled in the opening minutes, but then began to create chances. Toni Doblas tipped over a shot from Messi, while Jarosik had to be alert following a combination between Messi and Iniesta.

Messi shot at Doblas again before Zaragoza created their best chance and Braulio should have scored when clean through on goal only to scuff his shot straight at Victor Valdes.

Barca were enjoying 80 percent of possession, but didn' t score until the 42nd minute. Messi took a pass after a strong run from David Villa and calmly slipped the ball under the helpless Doblas.

Zaragoza needed to get into the game fast, but the second half got off to a dreadful start when Ponzio was sent off for hitting Dani Alves in an off the ball incident.

Replays showed Alves made a meal of the incident, but confirmed that the midfielder had clearly hit the Barcelona defender, who was nevertheless booed for the rest of the game by the home fans.

Zaragoza spent the rest of the game chasing shadows as Barcelona made the extra man count and keep possession. Doblas saved well from Messi in the hour and from Villa five minutes later.

He could do little with the rebound however, as Messi drilled home the loose ball to assure Barca' s fourth away win of the season.