The Pirates will try to keep a three-game winning streak going in their next matchup against the Colorado Rockies Saturday night at 7:05.

The Pirates defeated the Marlins 4-3 Friday, with Neil Walker and Pedro Alvarez hitting homers. On Saturday, they'll look for more of the same as Carlos Zambrano faces A.J. Burnett.

Zambrano has allowed three or more earned runs in each of his last seven starts. An ongoing problem with walks has contributed to that trend -- Zambrano is fourth in the majors in walks with 57 (behind Edinson Volquez, Ubaldo Jimenez and Ricky Romero and tied with Yu Darvish), and he's allowed at least two walks in every start going back to May 13. He's had more and more problems as the season has gone on, posting ERAs of 3.24 and 2.85 in April and May and 7.23 and 4.76 in June and July.

For more on the Pirates, check out Bucs Dugout.