By Morris Phillips

SAN FRANCISCO–On a wacky night like this, a pair of teams with .500 early-season records sure didn’t seem like equals.

The Giants followed a brief 3-3 road trip with the clunker of all clunkers in their return to AT&T Park Thursday night, a 17-7 loss to the Rockies, that if nothing else, showed vividly which of the middling NL West contenders is trending in the right direction, and which one is not.

The Rockies improved to 5-2 on their road trip—always an eye-opener for the Mile High-based club that has traditionally faltered on the road—while the Giants turned to Matt Cain, and saw him flounder from the third batter he faced, the 13^th consecutive start in which he has failed to record a win.

And while Cain could possibly label the 297^th start of his career his worst, it wasn’t as bad as Vin Mazzaro’s relief appearance in which he recorded just one out, while allowing nine of the 13 runs in Colorado’s record-breaking fifth inning.

And while a 13-run inning is a big story in itself, it’s merely a chapter in a bigger story for San Francisco: How far can the Giants go with Cain and Jake Peavy? The veteran pair have made a combined 12 starts, allowing 91 hits in 60 innings. As expected, manager Bruce Bochy said after the game, for the moment, the two veterans remain rotation members in good standing.

“It’s been encouraging at times, but at the same time, we know we have to get better there. And Matty will tell you the same thing, just like Jake. They’ve been around, they have experience. But right now, they’re our guys and we’re staying behind them.”

The 13-run inning was the biggest outburst of any major league club since 2010. It also marked the biggest inning in the history of the Rockies—Coors Field or not.   The 17 runs scored by Colorado was just two off the most the club has ever scored in a road game, only fewer than the 19 runs the Rockies scored on September 25, 2011 in Houston.

And while the big inning was surely unique, it must have felt oddly familiar to the Giants. Exactly a week ago, with Peavy on the mound, the Giants surrendered 12 runs in an inning to the Mets.

“It’s hard to believe lightning hit us twice here in about a week,” Bochy said.

Cain started off inauspiciously enough. He retired the first two batters, but then Carlos Gonzalez singled, and major league home run leader Nolan Arenado deposited a 2-0 pitch over the left field wall.   Gerardo Parra doubled, Mark Reynolds singled him home and just that fast the Rockies led 3-0.

The Giants responded with a pair of runs in the first, another in the second, to lessen the impact of Cain’s rocky beginnings, but after a couple of encouraging innings, rookie sensation Trevor Story touched Cain for a homer leading off the fifth, and the floodgates opened.

In all Cain, allowed 10 hits—half of those for extra bases—and six earned runs. Unable to record an out in the fifth, he was lifted, the third time the season the veteran has failed to finish five innings in a start.

Former Athletic, Vin Mazzaro, followed, and the Rockies methodically, and unemotionally, picked the reliever apart. Mazzaro faced 10 batters, allowing six hits, a walk, and nine runs, seven of those earned.

After being lifted, Mazzaro sat puzzled in the dugout, his facial expression resembling that of someone that had just witnessed a train wreck. As much as any Murderer’s Row can display modesty, the Rockies did, taking the whole 37-minute fireworks display in stride.

“Everybody was just putting good swings on the ball and having fun with it,” rookie Trevor Story said.

The Giants played without Hunter Pence, who suffered back tightness before the game, and Joe Panik, who’s sidelined with a groin issue. The poor pitching wasn’t their only issue; sure handed Brandon Crawford and Kelby Tomlinson, playing second base, made untimely errors in the fifth. Earlier, third base coach Roberto Kelly inexplicably sent Buster Posey home on Crawford’s single, challenging Gonzalez’ rocket arm with no outs. Posey was thrown out easily, and Mac Williamson followed by hitting an inning-ending double play ball.

Had the Giants pushed a run across in that third inning, it would have tied the game 4-4.

With the loss, the Giants fell into a three-way tie for first with the Rockies and Dodgers. All three have .500 records, but while the Dodgers and Rockies have winning records against NL West competition thus far, the Giants have dropped ten of 18 games within their division.

On Friday night, the Giants turn to Madison Bumgarner, coming off his impressive start in New York, in a matchup with Colorado’s Chad Bettis.