Walker threw 60 pitches over 3.1 innings in Sunday's intrasquad game, Shannon Drayer of 710 ESPN Seattle reports.
The right-hander had to work around some trouble in two of his innings, but he finished the outing allowing only three hits and three walks but no runs. Walker encouragingly also recorded three strikeouts and commented after the game that he felt strong and "definitely" would be ready for this first start of the season Saturday against the Astros.