Numbers don't do Robertson justice

The numbers don’t do David Robertson justice.

Nonetheless, here they are:

• He’s allowed just one earned run in his last 18 appearances since May 17 (17.1 IP, 9 H, 30 K).

• He's tied for the American League lead in holds (15) and has 50 strikeouts.

• He ranks first in the majors among pitchers who have thrown at least 30 innings in SO/9 (14.36).

And don’t forget: Robertson was supposed to be the Yankees’ sixth-inning guy.

“Our bullpen started off so deep, and we felt we had a number of arms that we could turn to late in games,” manager Joe Girardi said.

Then Rafael Soriano went down. Then Joba Chamberlain went down.

All of a sudden, Robertson found himself setting up Mariano Rivera -- a role he’s flourished in.

“Robbie has done a tremendous job in the eighth inning in the absence of Joba and Soriano and gotten some big outs, sometimes four or five outs, when we’ve asked him to do it,” Girardi said.

Just how good is Robertson?

Case in point: Rockies cleanup man Troy Tulowitzki battles Robertson for 10 pitches leading off the eighth, before Robertson finishes him off with a 92-mph four-seam fastball.

“Tulo kept going at him and going at him and he got him out,” Girardi said.

Last season, Matt Thornton, Evan Meek, Hong-Chih Kuo and Arthur Rhodes -- all setup men -- all made the all-star team.

Robertson certainly merits that consideration. He just needs some Houdini Magic.