In exchange for Norris, the Padres received right-handed pitching prospect Pedro Avila.
The acquisition of Norris represents a low-cost addition for the Nationals at a posititon of need. Wilson Ramos served the 2016 season as starting catcher in D.C., but he tore his ACL and is a free agent this offseason. The Norris trade likely means the Nationals will not be bringing Ramos back, even on a multi-year deal, which would allow them to have him back when healthy.
The Nationals' front office should already be familiar with Norris, who was a fourth round pick of the team back in 2007. He never made it to the big leagues with Washington, though, as he was shipped to the Oakland Athletics in exchange for Gio Gonzalez.
Last season, Norris had the worst offensive year of his career, hitting just .186/.255/.328 with 14 home runs and 42 runs batted in. Some of that can be attributed to a career-high strikeout rate (30.3 percent) and an extremely low BABIP of .238. Good defense, though, made him worth just -0.4 WAR, per FanGraphs.
If If Norris can have a bounce-back year offensively, the Nationals may be able to get some real value out of him. Norris, even when posting a below league-average 97 wRC+ in 2015, was still worth 2.4 WAR. (To compare, his wRC+ in 2016 was a dismal 55.)
As for the Padres, Aliva is something resembling a lottery ticket. Not listed on the Nationals' top 30 prospects (MLB.com), Avila pitched in Class A Hagerstown last season. He posted a 3.48 ERA and a 92-38 K/BB ratio over 93 innings, all as a starter.