Madonna's spiritual ties to mystical Kabbalah teachings have been partly blamed for baseball star ALEX RODRIGUEZ's marriage crisis.

The pop superstar was recently romantically linked to the New York Yankees star, but now it appears they are just two close friends who share the same manager.

However, as Rodriguez's wife Cynthia takes off to France to spend time with pal Lenny Kravitz, family and friends insist the baseball player's interest in Kabbalah, which Madonna reportedly introduced him to, has driven a wedge between the couple.

Speaking to America's Us Weekly magazine, Rodriguez's father-in-law has confirmed the baseball star is dabbling with Kabbalah.

John Scurtis says, "He's gotten involved in Kabbalah, which isn't something we understand. We don't really get that. My family is Greek Orthodox."

But Scurtis refuses to pass judgment beyond that, stating, "He's (Rodriguez) been very good to my daughter, and he's been very good to us. I hope they work it out."

A source close to the baseball star and his wife claims Rodriguez's Kabbalah interest has changed the sports star.

The insider tells the New York Daily News, "I don't recognise the man he's become. He was a sweet, beautiful, loving husband and father. Today, he's very cold and calculating."