The Washington Nationals, tied with Atlanta for first place in the National League East, begin a nine-game road trip Monday with the first of three contests against the struggling Colorado Rockies. "Any time you get a walk-off win, it's big for team morale," Washington reliever Drew Stammen told reporters after the Nationals defeated Milwaukee 5-4 on Sunday when Jayson Werth delivered a two-out RBI double in the ninth inning. "Hopefully, it will send us on a nice little winning streak." Washington, which has won four of its last five games, has a hot hitter on its hands as Ryan Zimmerman is 11-for-26 with two home runs and 10 RBIs in his last seven contests.Colorado, which has the worst ERA in baseball at 5.08, received three consecutive quality starts over the weekend in Pittsburgh but was swept despite leading in every game to extend its losing streak to five and fall to 4-23 in its last 27 contests. The Rockies were missing three regulars Sunday - shortstop Troy Tulowitzki (leg), first baseman Justin Morneau (neck stiffness) and outfielder Charlie Blackmon (ankle) - and all three are considered day-to-day. Washington's Doug Fister has won two straight starts and three consecutive decisions heading into his matchup with Franklin Morales, who has pitched well in two starts since returning to the rotation.TV: 8:40 p.m. ET, MASN (Washington), ROOT (Colorado)PITCHING MATCHUP: Nationals RH Doug Fister (8-2, 2.90 ERA) vs. Rockies LH Franklin Morales (5-4, 5.26)Fister allowed two runs and seven hits in seven innings of a 6-2 victory at Baltimore on July 9. "You don't ever feel like you're out of the game when he's out there,'' Werth told CSN Washington regarding the 30-year-old California native. "I think there's something about how he works. He works quick. He throws strikes. He keeps you on your toes." Fister is 2-0 with a 2.08 ERA and 0.85 WHIP in two career starts against Colorado but never has pitched at Coors Field.Morales yielded one run and four hits while walking three and striking out six in 5 2/3 innings of a 2-1 victory over San Diego on July 8 after receiving a no-decision in a 3-2 loss to the Los Angeles Dodgers five days earlier, when he allowed two runs (one earned) in five frames. It is a significant improvement as a starter for the 28-year-old Venezuelan, who posted a 6.13 ERA in his previous 11 turns this season. Morales, who is 5-0 with a 3.09 ERA in 43 2/3 innings versus the NL West and 0-4, 7.42 in 43 2/3 frames against everyone else, makes his first career start against Washington after five scoreless relief appearances from 2009-12.WALK-OFFS1. Washington 1B Adam LaRoche on Sunday snapped an 0-for-18 skid by going 2-for-3 with two runs scored and is 7-for-50 in July.2. Rockies RF Carlos Gonzalez is 5-for-25 with nine strikeouts in six games since missing 35 contests with a finger injury.3. Washington outscored Colorado 18-6 during a three-game sweep June 30-July 2 at Nationals Park.PREDICTION: Nationals 6, Rockies 2