LAS VEGAS -- Brandon Morrow, the fifth overall pick in the 2006 First-Year Player Draft, is going back to the Minors.

The Mariners optioned Morrow to Double-A West Tennessee and outfielder Jeremy Reed to Triple-A Tacoma after the 10-2 victory over the Cubs on Friday night.

Morrow was 3-4 with a 4.12 ERA in 60 relief appearances as a rookie in 2007. He was set back by a stiff shoulder and had a 10.80 ERA in five Spring Training appearances with nine walks in five innings. He walked three in one inning Thursday at San Francisco.

"Morrow is just not quite ready," Mariners manager John McLaren said. "He hasn't pitched back-to-back. His velocity is great. He's having problems with his delivery a little bit. We're going to put him on a throwing program, get to him where he's throws back-to-back. I see him being back fairly soon."

Morrow will return to Arizona to work out with the Diamond Jaxx until they break camp. Morrow pitched only one season in the Minors after being drafted, before making the 2007 Opening Day roster.

Reed, who at age 23, was the youngest player on the Mariners Opening Day roster in 2005. He hit .254 with 33 doubles that year. Reed started 2006 with a 10-game hitting streak, but then had an 0-for-21 skid in May and subsequently broke his right thumb, which needed surgery, diving for a ball in July.

He spent most of last season in Tacoma, hitting .300, but had just a .176 average in 13 games when he was called up in September. Reed hit .321 in 24 Spring Training games.