Walt Weiss is a rookie big league manager, so it wasn’t until last week when the Washington Nationals came through Denver that Colorado’s skipper got his first chance to see Ian Desmond in person. He’d seen the Nationals’ shortstop on television, and he’d studied him in his preparation for the series. Desmond, the Nationals’ most consistent offensive force this season, tore up the Rockies over their three-game series. In the midst of a 15-game hitting streak that culminated with a 4-for-4 afternoon at Coors Field, Desmond tagged Rockies pitchers for seven hits in 10 at-bats, drove in five and struck out only once. Weiss was awed. “Desmond’s a very impressive player,” Weiss, not one to embellish, said Thursday. “I was very impressed. He’s more physical than I realized. Really quick bat. “I think he’s a star in the making, if he’s not already.” On the heels of Desmond’s game-winning grand slam in Philadelphia on Wednesday night, the topic of just how big a star the Nationals’ shortstop is becoming was an intriguing one, albeit one the man himself doesn’t seem much interested in discussing. Desmond was an All-Star in 2012, but an oblique injury kept him from taking part in the game. His case to be one this season is strong, and made stronger by injuries to fellow shortstops Troy Tulowitzki of the Rockies (rib) and Everth Cabrera of the Padres (hamstring). Last year was Desmond’s breakout — the season so many had hoped to see from him — but what he is doing now is perhaps equally as impressive. In the midst of a career-high 52 consecutive errorless games, Desmond may be playing the best defense of his career. He leads all major league shortstops with 30 extra-base hits, and his seven game-winning RBI are tied with Tulowitzki for the most at the position. What he’s doing now is establishing himself as consistently elite. “I definitely consider him one of the best shortstops in the league,” said Rockies outfielder Michael Cuddyer, who put him in a select class with Orioles shortstop J.J. Hardy and his teammate, Tulowitzki. “He’s an aggressive offensive player and he’s gotten really good on defense as well,” Cuddyer said. “Ever since you saw those guys back in the late ‘90s with [Alex Rodriguez] and [Nomar Garciaparra] and [Miguel Tejada], you don’t see [slugging shortstops] very often anymore. It’s a rare combination and he’s extremely athletic. He can run, take extra bases, and all that plays into it as well.” Desmond’s offense, often one of few highlights in this much-maligned season for the Nationals, is his most overt quality. It’s easy to see the numbers — the .280 average, .477 slugging percentage and 10 home runs — and find him ranked among the best at his position. But it’s more difficult to quantify the quality of defense he’s been playing, particularly of late. “A couple years ago, the talk was about whether he could play shortstop,” third baseman Ryan Zimmerman said. “Last year, I know he didn’t win the Gold Glove but he did a lot of things that were at least in that category where he deserves the consideration every year. This year, he made a few errors in the beginning but then he’s really settled down.