Dodgers pick up left-handed reliever Tyler Olson from Mariners

The fringes of the Dodgers’ 40-man roster are always an interesting, if dangerous, place to be under Andrew Friedman & Co. Yesterday’s addition can quickly become today’s subtraction.

The Dodgers were at it again Friday, picking up left-handed reliever Tyler Olson from the Mariners for cash or a player to be named later and designating for assignment right-handed Danny Reynolds, a minor league reliever they had claimed from the Angels 11 day earlier.

Olson, 26, was a local product for the Mariners. He went to high school in Spokane, Wash., and pitched collegiately at Gonzaga before being drafted in the seventh round by Seattle in 2013. He made his major league debut with the Mariners last season, going 1-1 with a 5.40 ERA and a tough 2.10 WHIP in 11 appearances.

In 13 1/3 innings, Olson struck out eight but walked 10 (seven intentionally). In three minor league seasons he went a combined 17-17 with a 3.86 and 1.33 ERA.

Who knows how long he’ll remain on the Dodgers’ roster? The Dodgers already have left-handers J.P. Howell and Luis Avilan in their bullpen, and left-handed relievers Adam Liberatore and Ian Thomas on their 40-man.

Reynolds, 24, saved 10 games for double-A Arkansas last season, posting a 4.57 ERA.