The Nationals claimed Lara off waivers and optioned him to Double-A Harrisburg Friday.
The 23-year-old was designated for assignment by Atlanta on Wednesday and will remain in the National League East after being claimed by Washington. A change of scenery could be beneficial for Lara, who has struggled to an 8.22 ERA, 2.65 WHIP and 21:29 K:BB across 15.1 innings at the Double-A level this year.