All of the runs, as well as the walks, came in his final inning of work.
"I thought I actually threw the ball really well [Saturday]," Skaggs said. "Without that last inning, it's actually a really good outing. A very, very good outing."
It has been a struggle for Skaggs this spring as he has been outpitched thus far by Patrick Corbin and Randall Delgado as the trio battle for the No. 5 spot in the rotation.
"It's very frustrating to see the two guys you're battling with succeed and you want to succeed," Skaggs said.
Manager Kirk Gibson said he thinks Skaggs has been pressing too much.
"Seems like he's overthinking things," Gibson said. "He's very mechanical. Somehow we need to get him back to where he's just pitching. He came out throwing the ball decent [Saturday]. Last inning, though, he just totally lost it. He just had a lot on his mind."
Said Skaggs, "I wouldn't say I'm putting too much pressure on myself. You're going to think that you want to do well, that's just human nature, and you want to win a spot, that's also human nature. I'm just not having the results that I want."
Steve Gilbert is a reporter for MLB.com. Follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.