Muscle man Ryan Phillippe steps out with his new leading lady Amanda Seyfried

If Amanda Seyfried was looking for a strong man, she seems to have found him.

The Mamma Mia! actress was spotted on a shopping trip with her new boyfriend Ryan Phillippe, who put his muscle-bound arms on show in a white vest.

While the Cruel Intentions star looked every inch the Hollywood heartthrob, Amanda looked a little dishevelled in a grey T-shirt, shorts and unbrushed hair.

Mr Muscle: Ryan Phillippe joined Amanda Seyfried on a shopping trop to Fred Segal in LA on Monday

The pair went stopped in a popular boutique Fred Segal in West Hollywood before the 36-year-old actor dropped off Amanda, 25, at a friend’s house.

The night before, Ryan made a solo appearance at a Golden Globe Awards after party at The Beverly Hilton Hotel.

The couple have been quietly dating since they first met at a Halloween party at Kate Hudson's house last year.

Getting serious: The actress is 'smitten' with her new man, according to insiders

A source tells Hollywood Life: 'Amanda’s smitten. Ryan is very charming and he brings out a very giddy side in her. '

Amanda previously dated British actor Dominic Cooper, 32.

They had an on-again off-again relationship after meeting on the set of the 2008 film, Mamma Mia.

Ryan dated Australian actress Abbie Cornish after his marriage to Reese Witherspoon ended in 2006.

Reese, 34, who is the mother of his two children Ava, 11, and Deacon, seven, is now engaged to Hollywood talent agent Jim Toth.