Lopez, in the closing role because Rafael Betancourt needed a day off after notching saves in each of the past two games, gave up two runs in the ninth inning and the Arizona Diamondbacks rallied past Colorado 5-4 Sunday, stopping the Rockies' eight-game winning streak.
"This is a good team and we battle every single game," said the Rockies' Carlos Gonzalez, whose two-run single boosted his league-leading RBI total to 21.
"If you're going to lose your winning streak, it's better to do it the way we did today, playing good baseball," Gonzalez added. "We just had one bad inning at the end. Our closer was not available today, but I know that Wilton is going to get better. He's just having a bad start. But he's done it in the big leagues. he's going to pitch well."
Didi Gregorius, who homered Thursday at Yankee Stadium in his Diamondbacks debut, started a comeback from a 3-0 deficit when he homered against Juan Nicasio leading off the fifth.
Colorado led 4-3 when Gregorius singled leading off the ninth against Lopez (0-1), who was acquired in an offseason trade with Houston. A.J. Pollock bounced a double that just barely sailed over the head of leaping third baseman Jonathan Herrera.
"It was a weird play, another weird hit off of Wilton," Rockies manager Walt Weiss said. "He's had a lot of them this season.
Pinch-hitter Alfredo Marte then grounded out to third, driving in the tying run and costing Lopez his second blown save this season.
Weiss was asked whether Herrera should have gone home with the throw instead of first.
"It's tough to say without seeing a replay," Weiss said. "He obviously didn't think he would get there (to home) in time. It's a tie game at that point and we'll take our chances in the ninth."
But it didn't stay tied.
Gerardo Parra followed with a sacrifice fly to deep center.
Heath Bell (2-0) pitched a scoreless eighth. Colorado put runners at the corners in the ninth before J.J. Putz got Eric Young Jr. to hit a game-ending comebacker for his third save in five chances.
"The whole bullpen gave us a chance," Bell said. "Matt Reynolds did well before me. And J.J. after me. We wanted to keep the ball down. The Rockies were on fire. And we knew we had to make pitches."
Arizona improved to 6-0 in getaway games this year.
Colorado lost for the first time in nine games at Coors Field.
Adam Ottavino relieved starter Nicasio in the fifth and Josh Outman got the last two outs of the seventh.
Colorado strung together four consecutive singles in the third off Brandon McCarthy, building a 3-0 lead on Jordan Pacheco's RBI single and Gonzalez's bloop two-run single that dropped into shallow center field.
Nicasio struggled with his control despite not allowing a hit until the fifth. He threw 49 pitches in the first two innings, when he walked three and went to three-ball counts on two other batters.
"I need more command of my fastball," Nicasio said. "I've thrown like 90 pitches in the last three games and only gone five innings. I've got to go deeper in the game."
Gregorius homered off Nicasio to start the fifth for the Diamondbacks' first hit, and Pollock's single and Parra's one-out doubled chased Nicasio. Martin Prado reached on a comebacker to Ottovino, who tagged out Pollack after the runner broke for home, and Paul Goldschmidt followed with an RBI single that cut the gap to 3-2.
Troy Tulowitzki homered on a 1-2 pitch leading off the sixth, and with six home runs already is just two shy of his total last year.
Cody Ross hit a two-out RBI double in the eighth against Matt Belisle.
NOTES: Eric Young Jr. caught the ceremonial first pitch from his younger brother Dallas and his father, former Rockies player Eric Young, on the day the club honored the senior Young with a bobblehead doll giveaway. ... McCarthy allowed four runs and eight hits in six innings. ... The Diamondbacks return home to face the San Francisco on Monday with LHP Wade Miley (2-0) slated to pitch the opener against the Giants' Ryan Vogelsong (1-1). ... Colorado opens its series against the Braves on Monday with LHP Jeff Francis (1-1) facing Atlanta's LHP Mike Minor (2-1). ... The Rockies placed Jhoulys Chacin on the 15-day DL with a back strain, a move retroactive to Saturday. They recalled RHP Rob Scahill from Triple-A Colorado Springs.