Friday's baserunning blunder wasn't the only reason the Cubs designated backup outfielder Julio Borbon for assignment. But it was the final straw. Borbon hadn't been much help since the Cubs picked him up off the waiver wire in April. He had a hitting line of .202/.284/.279 with 22 strikeouts in 104 at-bats. He also didn't play a very good outfield despite his speed. The Cubs sent him away Friday night hours after he was thrown out trying to go from second to third on a ball in the dirt with the Cubs down 6-2 in the ninth inning with nobody out. Manager Dale Sveum was as upset about that play as he was about any this season and his bosses seemed to agree. "We always talk that we have to play more airtight baseball" said general manager Jed Hoyer. "Every team has their bad games or bad moments but that was a situation where they (the Dodgers) didn't have their closer in the game. We gave up an opportunity because of a bad baserunning play. Obviously every time a guy makes a mistake you're not going to make that decision. We felt like it was the right message to send." Sveum said there's a difference between physical errors and mental errors.