An open letter to our nice little local nine:

OK boys, you've won eight straight, have added an All-Star closer and moved within a half-game of first place.

Now it's time for you to show us something.

Show us you can compete with the big boys.

Strangely, the challenge in this case resides in a decrepit stadium in St. Petersburg, Fla., in the form of the formerly forlorn Tampa Bay Rays.

The Rays, though, are the last team on the Twins schedule winning 60 percent of its games, the last team on their schedule that has proved it belongs in the same class as the Twin-tormenting Yankees.

The Rays have built the second-best record in baseball, right behind the Yankees, and feature the kind of power pitching, speed and versatility that makes them the most exciting team in the game.

Even if the Twins win the American League Central, they will enter the playoffs with a reputation for losing playoff series, and for playing poorly when in the presence of pinstripes.

Beating the Rays this week wouldn't change that perception, but it would validate the Twins' recent domination of the Three Stooges of the American League (Baltimore, Kansas City and Seattle) and bolster the Twins' confidence for the stretch run.

Beating Seattle requires a pulse. Beating Tampa Bay requires heart.

Recent Twins history tells us that this team is capable of arrhythmia when in the presence of superior teams from the AL East, particularly when playing in New York or Boston.

Tampa Bay is just as elite if not as renowned as the Red Sox and Yankees, but then the Twins, after stumbling through June, are positioned to play their best baseball down the stretch.

Danny Valencia has exceeded the expectations of even the Twins' brain trust, handling third base with ease and swinging with more authority in the past two weeks.

"Valencia coming up and stepping up has really been nice," Twins manager Ron Gardenhire said. "I'm so happy with his defense. He's playing the heck out of third base, and that's huge. He's going to get his hits, the question is whether he would be able to play defense up here."

Delmon Young has become an MVP candidate. Carl Pavano has become an ace. Francisco Liriano has become a workhorse. Brian Duensing has tossed a lifebuoy over the back end of the rotation.

Duensing's departure from the bullpen created a lack of depth that was assuaged by the trade for closer Matt Capps, and Glen Perkins could soon take Duensing's former role as a key lefthanded reliever.

When Justin Morneau and Orlando Hudson return from the disabled list, the Twins will field the deep lineup and impressive roster they thought would give them a chance to win their first playoff series since 2002.

"When Justin gets back, it's going to be entertaining," Gardenhire said. "I can't wait to get them all back, to where you know we'll have a bench, a solid bench, and you'll have a lineup that I can run out there that will be solid. ...

"We're playing pretty good baseball, but I'd like to see us when we get all of our chips out there at the same time again. I really liked us early in the season, the first month or so when everybody was healthy and out there playing, we were going along pretty good."

With Morneau and Hudson healthy and Valencia producing at third, the Twins could field their deepest lineup since the late '80s. The addition of Capps gives the Twins a proven closer and bullpen depth, one of the great indicators of late-season success. Duensing's transition gives the Twins starting pitching depth and a fresh arm for the stretch run.

Four months into the season, the Twins are right where they were when they started. They are promising yet unproven and looking to establish themselves against baseball's elite.

They can do that by beating up Tampa Bay. Getting swept wouldn't ruin their season, just reaffirm their reputation as a nice little team built for Midwestern races, not World Series runs.

Jim Souhan can be heard at 10-noon Sunday on AM-1500. His Twitter name is SouhanStrib. • jsouhan@startribune.com