"They are definitely less severe and definitely less frequent," said Roberts, who has consulted with other players who have had concussions, including the Minnesota Twins' Justin Morneau and the Toronto Blue Jays' Aaron Hill. "In May and June, my symptoms were much, much worse. I wasn't participating in anything because my symptoms at that point were so bad that I wasn't capable of participating in activities, really. … I've been doing baseball activities off and on for the last couple of weeks, and we've made some pretty good progress. I'm not to the point where I can do everything that we need to do, unfortunately, yet, but we're a lot farther along than we were a month ago."