WICHITA -- It wasn't so much a rallying cry as it was a gentle reminder: Take it easy. Have some fun. And please don't pull anything.

"There's a lot of guys here that have a lot of experience in the big leagues, for sure," said Roy Oswalt, a former three-time All-Star with the Houston Astros. "It's just the age factor is playing against us a little bit."

There were plenty of Old Man jokes floating around in the hours leading up to the Kansas Stars debut against the Sterling, Colo., Xpress on Saturday at Lawrence-Dumont Stadium in Wichita, Kan. That was to be expected, given the Stars roster was almost exclusively comprised of former Major League players, most of whom have been retired from the game long enough to know shaking off the proverbial rust may require a little extra time.

"Even when I retired, my arm felt great," Oswalt said. "It was just other parts of my body that didn't want to hold up too well."

Oswalt is one of approximately 25 former Major Leaguers who are in Wichita this week to play for the Stars in the NBC (National Baseball Congress) World Series, an 83-year-old wood bat tournament that attracts college-age ballplayers from all over the country. The Stars, scheduled to play again on Monday and Wednesday, are one of 16 teams participating in the tournament, but for obvious reasons, their presence has created lopsided attendance figures.

Saturday night's game, an 8-0 Stars win featuring stellar pitching by four-time All-Star Tim Hudson and 2003 World Series MVP Josh Beckett, was a sellout. The other two games are expected to draw the same.

"The last time I pitched to a hitter, it was my 12-year-old son," Hudson joked before the game. There was no need for worry. Hudson, whose final Major League appearance was in 2015, breezed through three hitless, scoreless frames, striking out three.

No one was in more awe of the 17-year veteran and winner of 222 Major League decisions than the Xpress players who could do nothing against him.

"It was the experience of a lifetime to face Tim Hudson." Xpress infielder Lucas Lingreen said. "I swung through three of his sliders for a strikeout. It's pretty filthy. It's awesome."

Said Hudson: "It was a lot of fun, it really was. Obviously we're probably not in the kind of shape we'd like to be for the duration of a game, but for an inning and a third, inning and two-thirds, I felt like pretty good. Then, someone tied an elephant to my back and it was a little challenging after that."

In total, members of the Stars roster have played in a combined 103 playoff series and 30 All-Star Games. The team features three former Silver Slugger winners and seven-time Cy Young recipient Roger Clemens, who is expected to appear for an autograph session on Monday and pitch in Wednesday's game.

More impressive names are peppered throughout the roster. Jason Marquis. Heath Bell. Brad Penny. Brett Tomko. Jason Isringhausen. Jack Wilson. Adam LaRoche. Dan Uggla. J.D. Drew. Brandon Inge. The only two non-Major Leaguers, in fact, are Clemens' son, Koby, and country music star Toby Keith, who is listed on the official roster as an infielder, wearing uniform No. 10. (For those keeping score at home, he bats and throws right-handed.)

The Stars' idea was the brainchild of Nate Robertson, who played nine years with the Marlins, Tigers and Phillies, and LaRoche, a veteran of 12 big league seasons, who retired earlier this year following a controversial Spring Training with the White Sox. The two Kansas natives began contacting retired players whom they thought might be interested, needing very little time to find enough to form a team.

"I said, 'Sure, why not?'" Oswalt said. "It kind of grew legs and somebody else called somebody else and next thing you know we got a team together."

While it's easy to joke about these players being past their prime, in truth, most of them are still in their 30s, and all are in very good shape. Only Hudson (41), Drew (40), Isringhausen (43), Tomko (43) and Clemens (54) are 40 or older. In fact, everyone on the roster is younger than Clemens was when he retired from the Majors at age 45 in 2007.

Committing to play was one thing. Preparing to play was quite another. Oswalt, only three years removed from his final game as a big league pitcher and a few weeks shy of his 39th birthday, started throwing side sessions about a month ago and squeezed in a round of batting practice to hitters when he was in Round Rock to be inducted into the Express' Hall of Fame (the Express was the Astros' Double-A affiliate when Roy was a minor leaguer, before the team's name was changed to the Xpress).

"I think I got five bullpens in," Oswalt said. "You never know what you're going to get when you get back out there."

Penny, 38, who pitched 14 seasons in the big leagues and pitched in five postseason series, took a more laid-back, humorous approach with his preparation.

"I don't know what to expect," he said. "I retired because it hurt. To come out here...I told them in the clubhouse, 'Next time, let's just go to Hawaii or something.'"

After the game, LaRoche wasn't so much focused on the Stars as he was on their opponent, an Xpress team filled with wide-eyed youngsters who proved to be formidable foes during a game that lasted well past midnight.

"I don't know how hard he was throwing," LaRoche said of starting pitcher David Mendez. "I felt it was 99 my first at-bat. I liked him. He looked like he was enjoying it. He had a great attitude.

"It was really cool to be at first [base] and get to talk to those guys and just how appreciative they were. I told them, 'Thank you for letting us come and do this.'"

***

Alyson Footer is a national correspondent for MLB.com. Follow her on Twitter @alysonfooter.