The bullpen failed again in the eighth when Michael Bowden gave up a single, wild pitch and the eventual winning run on John Jay's base hit.
Villanueva, who is 1-2 with a 3.02 ERA, has left five of his seven starts with a lead, and the bullpen has blown four of those five games.
"There are going to be days out there where we (starting pitchers) will struggle and the offense will pick us up," Villanueva said. "The good teams find that time when they (offense and pitching) are both in tune and win 20 or 30 ballgames while getting up there in the standings."
No such pipe dream exists for the Cubs right now. They have imploded on defense, offense and in the bullpen in a good majority of their losses. In 21 quality starts this season, Cubs starters have compiled an ERA under 2.00 yet have just eight wins to show for it.
"We just can't seem to shut anybody down in that sixth, seventh, eighth inning right now," manager Dale Sveum said. "We are getting two strikes on people. We just can't make a pitch when we have to."
Kyuji Fujikawa will rejoin the team in Washington after successful rehab outing in Tennessee (two innings, no hits). That will make both Wednesday's losing pitcher Bowden and the ineffective Shawn Camp vulnerable for a possible release.
The consistent losing is not on the bullpen alone. Cubs hitters were 1-for-9 with runners in scoring position on Wednesday. Overall the Cubs are batting .183 with RISP, the lowest in the major leagues.
"We seem to talk about these same situations a lot," Sveum said. "Today they seemed to get balls up to hit and we were swinging at balls below our knees in those big situations when we just needed a fly ball."
The Cubs made their 29th error on Wednesday tying them for the most miscues in the major leagues with the Miami Marlins.