A person with knowledge of the trade says the San Francisco Giants have acquired left-handed starter Matt Moore from the Tampa Bay Rays for third baseman Matt Duffy.

The person spoke on condition of anonymity because neither club had formally announced the swap. San Francisco already acquired reliever Will Smith from the Brewers to bolster their bullpen, and now they have a reliable addition for the rotation to join Madison Bumgarner, Johnny Cueto and Jeff Samardzija given the struggles of Matt Cain and Jake Peavy.

The 27-year-old Moore is 7-7 with a 4.08 ERA in 21 starts and 130 innings.

Duffy had a standout rookie season a year ago but has been hampered by an Achilles strain suffered against his new Rays team on June 19.