He's exasperated the followers of both the St. Louis Cardinals and Chicago Cubs with his penchant for imploding at the most inopportune moment.

Maddeningly inconsistent. Fragile of psyche. Just plain goofy.

Yet there he sits atop the National League list for victories. Yes, Jason Marquis has won 11 games for the Colorado Rockies and has been selected to the NL All-Star team.

The Rockies' right-hander has fashioned an 11-5 record and a solid 3.61 ERA. Marquis will be in uniform on Tuesday in St. Louis. Ask any Cards or Cubs fan in April about Marquis being at Busch Stadium for the Midsummer Classic, and you would have gotten a snide remark such as "only if he buys a ticket."

The rap on Marquis has been he isn't dependable. Hand him a 5-0 lead and Marquis will find a way to blow it. If your bullpen needs a break, count on Marquis to get knocked out in the third inning.

Marquis was acquired from Atlanta in a December 2003 trade that also brought Adam Wainwright to St. Louis. He was 28-21 over the next two seasons before his ERA ballooned to 6.02 in 2006. Despite 14 regular-season wins, Marquis was left off the playoff roster and could only watch as the Cardinals charged to the World Series championship.

After signing as a free agent with the Cubs, Marquis was a respectable 23-18 in 2007 and '08 with the Cubs. But his ERA sat above 4.50 both seasons, and Chicago was thrilled to deal Marquis and the final year of his dubious three-year, $21 million contract to Colorado for journeyman reliever Luis Vizcaino.

While a change in address to Coors Field didn't figure to boost his value, Marquis carries his best ERA since 2001 while making ample use of his trademark sinker. Maybe Jason has finally arrived at the realization that sinkers at the knees don't travel as far as mediocre, waist-high fastballs.

Marquis has received ample run support in Colorado and an effective first half is hardly a guarantee of a similar second half. But Marquis is an All-Star. And miraculously he deserves the honor.

St. Louis manager Tony La Russa, an All-Star coach, will be in the same Busch Stadium clubhouse as Marquis next week. It's a safe bet La Russa is flabbergasted at the prospect.