The Hammers boss believes that the 31-year-old is well-suited to West Ham's style of play and with his robust and committed attitude will be a favourite with the Upton Park faithful.
"Mauricio is a real winner," said Alan, "and he'll be a fantastic addition to our squad. He's a gritty, determined defender, but he can also play with the ball at his feet, and he should fit into our style of play very well.
"I signed him because I thought it was necessary to add a defender to the squad, with Malky Makay and Christian Dailly injured and also Hayden Mullins suspended.
"Mauricio can play anywhere across the back-four and is a great competitor, who will give us a lot of strength in defence.
"But he will also make a difference at the other end of the pitch. He likes to get forward from full-back and I think he'll bring more potency to our attacking play as well.
"We have some excellent strikers at the Club, who are capable of scoring goals, and I think by adding a player like Mauricio who can get forward from the back, it will help to create chances for them.
"I'm sure Mauricio will be a popular player at the Club, and with a few of his old team-mates like Sergei Rebrov, Teddy Sheringham and Matty Etherington around he'll settle in very quickly."
Looking ahead to this Sunday's London derby clash with Millwall, Alan admits that Mauricio will be in for a tough debut, should he play.
"He is the sort of player that will enjoy a derby fixture," said Alan. "He has experience of the North London derbies from his time at Spurs and he'll be very aware of what the occasion means to everyone.
"Sunday's game will call for the players to show grit and character, and that is the way Mauricio plays."
Alan also revealed that he is hoping to sign defender Darren Powell on loan from Crystal Palace, and the 28-year-old may yet arrive in time to be involved in Sunday's game.
"You need a big centre-half in this division," added Alan, "and Darren at 6ft 3ins is certainly that. He's a real warrior, another player with a lot of character, and hopefully we can complete his signing.
"I know him from my early days at Reading, and I even played Sunday League football with him towards the end of my career. Although, he's suffered with injuries Darren is now fit again, and if he joins I'm confident he'll do a very good job for West Ham United."