DENVER -- There are wins.

And there are BIG wins -- even in May.

There are nights like the Rockies' 5-4, walk-off victory against the Giants at Coors Field on Monday. It was only the 46th game of the season for the two teams. That does leave 116 games remaining for both.

But when a team is looking to shake off the negative image of back-to-back last-place finishes, every win helps. Some help more than others.

''Any time you win in the last at-bat, it is big and I don't care what time of year it is,'' said Rockies manager Walt Weiss. ''When you combine that with the fact we're going against a team in our division, one that's in first place.''

Enough said.

The three-game series that opened on Tuesday night isn't just a mid-week early-season event. It's a chance for the Rockies to step up and prove it. They have been saying that since the start of Spring Training that they felt they had better depth than ever before, and that they could withstand injuries that have ruined seasons past.

Now is the time to put up or shut up.

They are, after all, at home, where they have won each of the seven previous series, and where they are now 16-6, a .727 home winning percentage, second best in the Major Leagues to Miami's .739 (17-6).

The Rockies had every reason to jabber on Monday.

After former Rockie Tyler Colvin sliced a go-ahead double down the left-field line with two outs in the top of the ninth, the Rockies answered with a two-out, two-run Nolan Arenado double off the left-field fence in the bottom of the ninth.

And that came on the heel of Justin Morneau's game-winning two-run home run in ninth inning of Sunday's 8-6 win at Cincinnati. The Rockies are now within two games of the first-place Giants in the NL West, and with a chance to pull even if they could somehow pull off a sweep of this series.

''It doesn't matter if it is May or September,'' said left fielder Carlos Gonzalez, who singled ahead of Arenado's game-winning delivery. ''Every time you play within your division, it is real special, especially against the Giants. It's even more special.

''We are playing good baseball right now. We had a chance to do something specially.''

The Giants are special.

The Dodgers may have the biggest payroll in baseball, but it's the Giants who have won World Series championships in two of the past four seasons. They are the only NL West rival that has finished ahead of the Rockies in the standings each of the last five seasons. And they have made life miserable for the Rockies ever since Colorado debuted as an expansion franchise in 1993.

The Rockies all-time .432 winning percentage against the Giants (149-196) is lower than against every other NL team except Atlanta (61-110, .357) but then the Rockies did go 0-13 in their first year against the Braves, and were only 6-30 the first three years combined.

And the last couple of years, the Rockies haven't really done much against anybody. In finishing last in the NL West each of the last two years, the Rockies .426 winning percentage (138-186) is the 13th worst in the NL, better than only the Cubs (.392) and Miami (.404).

''It doesn't matter what outsiders might think,'' said Michael Cuddyer. "The thing we worry about is proving on own behalf.''

The Rockies have talked bravely in years past, but things have gone wrong early and the team has faded. They were beset by injuries each of the last two seasons, but couldn't meet that challenge.

They have had their problems this year, too, but they haven't got off track. They have had at least two of the projected five members of their starting rotation on the disabled list since the season opened, and Cuddyer, the defending NL batting champ, returned to the lineup Tuesday after four weeks on the disabled list.

''This year, we've overcome those things,'' said Cuddyer. ''That helps [build confidence] when you deal with that situation.''

That's what the Rockies had in mind during an under-the-radar offseason where they were looking to add quality veterans, even if they didn't grab headlines with their every move. There were trades that brought in right-hander Jordan Lyles and outfielder Brandon Barnes from Houston, left-hander Franklin Morales from Boston, and outfielder Drew Stubbs from Cleveland. There were free-agent signings of first baseman Justin Morneau, left-handed reliever Boone Logan, and closer LaTroy Hawkins.

So far, all the parts seem to be fitting together.

''This type of game,'' Stubbs said on Monday, ''is the type of game that pulls a team together. The past is the past. We have a new identity. We have a new team. This is a new season.

''There's probably a bad taste in some guys mouths, but the new guys that were brought in are veteran guys who have been with good clubs. When you have them around, it changes the culture. It changes the team's identity.''

It's a change the Rockies are enjoying.

They, however, have 116 games remaining on the regular season schedule to prove that they can walk the walk, as well as talk the talk.