HOUSTON -- Monday night essentially summed up the maddening enigma the Reds have been this season.It wasn't just that the Reds lost another heartbreaker -- this time a 4-3 defeat to the Astros in 10 innings. It wasn't just what they didn't have over the first nine innings -- a clutch hit, as they were 3-for-17 with runners in scoring position. It's the inability to sustain a spark. Two weekends ago, the Reds took two of three from the National League Wild Card-leading Braves. That was followed by being swept in a four-game home series by the wayward Mets. Next was a should-have-been-boost-providing three-game sweep of the world champion Giants this past weekend. And now this: a loss to a very young Astros team with a gutted lineup and unfamiliar group after the trades of Hunter Pence and Michael Bourn and demotions of two other players. "We take two or three steps backwards. Two or three steps forwards and one step backwards," Reds manager Dusty Baker said. "It's very frustrating. We've lost games in a number of ways." Taking over in the bottom of the 10th in a 3-3 game, Reds reliever Logan Ondrusek struggled for the third time in a week. Ondrusek gave up back-to-back singles on line drives by Humberto Quintero and pinch-hitter Angel Sanchez on a hit-and-run to put his team in dire straits. Brian Bogusevic was walked intentionally to load the bases with no outs. With the infield and outfield playing shallow, Jose Altuve scorched a liner up the middle. Second baseman Brandon Phillips made a spectacular diving stop and fired a low but on-target throw home. As he stretched at the plate, catcher Ryan Hanigan could not keep the ball in his glove and Quintero came in standing up. "It was a great play," Baker said "At that point, I thought we had an out there, maybe a double play to get out of the situation. Everybody's heart sank when the ball popped out. It's a tough way to lose. We've had some tough walk-offs, but not one like that." "When he caught the ball, I was like, 'Wow,' but as soon as I saw the ball on the ground and we won the game, it felt very good," said Altuve. And with that, the 53-56 Reds are a season-high 7 1/2 games behind the first-place Brewers. Milwaukee beat the second-place Cardinals and the third-place Pirates also lost, which means the Reds missed a chance to move one game behind Pittsburgh. "Any way you cut it, there's not a lot of games left," said starting pitcher Bronson Arroyo. "We've got to gain ground quick." One dropped ball was not the difference in the game as much as one missed opportunity to score after another. Ten men were left stranded. "We had some chances and didn't come through," Phillips said. In the Reds' third inning against Bud Norris and in a 3-0 deficit, Drew Stubbs led off with a single to left field and scored on a one-out double by Joey Votto. A Phillips RBI single to center field made it a one-run game. But the rally ended on a double play when Jay Bruce struck out and Phillips was caught stealing second base. Cincinnati missed more middle-inning chances against Norris, who gave up 10 hits over five innings before exiting in the sixth with a blister on his right middle finger. There were runners on second and third with one out in the fourth inning and no one scored. The bases were loaded with no outs in the fifth but only one run -- Miguel Cairo -- came home on Bruce's 4-6-3 double play to make it a 3-3 game. A runner on third base with one out in the sixth was stranded. There was a runner on second with one out in the top of the ninth and nothing came from that either. "We could have had a ton of runs," Baker said. "But when you keep a team like that close, anything can happen. When they stay close, they can beat you. We had an opportunity to blow that game open, many times." Struggling with a 0-3 record in his previous five starts, Arroyo had one of his best outings of the season. He tied a season high with eight innings pitched and allowed three runs with six hits, two walks and three strikeouts while retiring 13 of his last 14 batters and 18 of 20. For the first time since June 13, he did not allow a home run. But the three runs all scored in Arroyo's one not-sharp inning -- the bottom of the second. After two singles, Jimmy Paredes' first big league plate appearance went for a two-run triple to the wall in right-center field. Quintero's double off the outstretched glove of Stubbs in right-center field added the third run. "I've had my back against the wall a lot lately," Arroyo said. "I'm just trying to survive out there. I was happy to go deep in the ballgame and give us a chance to win. It's not any more satisfying really at this point in the season, seeing how many games far back we are. We need every win we can get regardless of how well you throw."