Bud Black is going to need his best players at full strength not just in September, but from now until September. If Colorado is going to stay atop the NL West and make Rocktober a reality, they’re going to have days like Sunday. In the series finale with the Cubs at Wrigley Field, Black rested Nolan Arenado and went to the ‘B-squad’ in his bullpen in a 7-5 loss. Still, Colorado won the series 3-1 and remains the best team in the National League at 41-24.

Rockies starter Antonio Senzatela struggled in the first inning, allowing four runs on four hits to put Colorado in a hole early. Fortunately, the Rockies would battle back to tie the game and chase Cubs starter Jake Arrieta, but Colorado’s bullpen couldn’t contain the Cubs down the stretch. Senzatela lasted just four innings, his shortest outing of the season. Instead of going to his middle-innings ace Chris Rusin, Black handed the ball over to Jordan Lyles who served up two solo home runs over 1.2 innings pitched to take the loss. Mike Dunn earned three outs over parts of two innings before giving way to Chad Qualls, who also allowed a solo home run in the loss. Six of Chicago’s seven runs came off home runs.

Colorado put up the bulk of its offense in the fifth inning. Tony Wolters led off with a double. Arrieta would give free passes to the next three he faced. Raimel Tapia followed with a walk. Charlie Blackmon was hit by a pitch and DJ LeMaheiu walked to get Colorado on the board. After Carlos Gonzalez struck out looking and was thrown out for arguing balls and strikes, Mark Reynolds singled in Tapia to chase Arrieta. Ian Desmond had a two-run single to tie the game. LeMahieu drove in Blackmon in the ninth inning, but Alexi Amarista flew out to end the game. Arenado struck out in a pinch-hit appearance in the ninth.

The Rockies will next head to Pittsburgh, the last-place team in the National League Central at 28-35. Kyle Freeland (7-3, 3.34) will try to match Senzatela with the team lead in wins for Colorado. Jameson Taillon (2-1, 3.31), who like Colorado’s Chad Bettis is recovering from testicular cancer, goes for Pittsburgh.