''Bryce is a little tick off (his timing),'' Williams said before the game. ''We certainly want to get him going. He needs at-bats. Yesterday I thought, we get him an opportunity to potentially get some good fastballs to hit.''
Since his return, Harper is 3 for 15 with an RBI and two runs scored.
''He's a little jumpy still, so he's continuing to work on it,'' Williams said. ''We'll get him back down to sixth today and let him go.''
Cubs right-hander Carlos Villaneuva starts Saturday in place of Jeff Samardzija, whose trade to the A's was confirmed earlier in the day.
Harper, who missed 57 games because of a torn ligament in his left thumb, hit sixth against a trio of Colorado lefthanders in his first three games back this week, with Rendon batting second.
Washington won all three, averaging six runs per game.
''I think it's just lack of at-bats,'' Williams said of Harper's struggles. ''You take that time off it's difficult. He'll be fine, he'll get it and it'll come quickly.
''Yesterday he was a little jumpy, and I can understand with that guy (Hammel), because he's got really good stuff.''
Harper is hitting .276 with a homer and 10 RBIs.