Kate Hudson swings her bat

Kate Hudson has reportedly been taking baseball lessons.

The 30-year-old actress has been learning the rules of the American sport to impress her boyfriend Alex 'A-Rod' Rodriguez, who plays for the New York Yankees.

"Kate is very smart. She knows that all good relationships are built on more than sex. Eventually, you have to talk," a source told the Chicago Sun-Times newspaper.

"And Kate realises that a key to keeping Alex is to be well-informed about his career and baseball in general - his first main love."

Kate didn't know much about the sport until she began dating Alex earlier this year. When she realised their romance was getting serious, she reportedly asked step-father Kurt Russell to explain the rules to her.

It has been claimed she is keen to take the relationship to the next level by getting engaged, and believes Alex is more likely to pop the question if she takes an interest in his professional life.