"Don't ever play him in Madden," Walker jokingly warned. "We were playing one day (last year) and he started talking about all these different defensive schemes ... just out of the blue."
Video games aside, Rapada knows a rat – and a rut – when he smells one.
Take for instance his struggles in Spring Training.
Having been added to the Cubs' 40-man roster just before the annual Rule Five Draft last December, Rapada had hoped to challenge for one of the few spots open in the Chicago bullpen in big league camp.
Instead he found himself in minor league camp early on, destined for a second stint at Triple-A where he spent the second half of 2006.
Rapada's first month back with Iowa is one he'd like to forget. He gave up seven runs on nine hits in 10 1/3 innings, and the reason was simple.
"It was all a mental thing," Rapada admits.
Now Rapada has started to turn some of his old tricks, and he believes that he has whipped the mental quirks.
He's allowed two hits in his last six appearances from the Iowa bullpen, where he has tossed 7 1/3 consecutive scoreless innings. His team has won seven straight games following an 11-5 victory over Fresno on Thursday.
"I was trying to pinpoint a lot of stuff and it was taking away from the action on the ball," Rapada explained. "That's where my money's at – with my sink. When I try to take a little off and be too fancy, I get out of my game."
Rapada's game is simple: throw strikes, limit the walks and stay out of trouble. That approach has helped carry him to Triple-A after being signed as a non-drafted free agent five years ago in 2002.
With Double-A West Tennessee last year, Rapada held opposing hitters to a .192 batting average and sported a 0.82 ERA in 33 relief appearances before getting the bump up to Iowa some time in late June.
But in big league camp this year, Rapada learned a quick lesson: facing major league hitters, even in Spring Training, is a long way from Double-A.
"Being that it was my first experience facing big league hitters, I was trying to do too much as opposed to doing all of the things that got me there in the first place," he said.
Rapada, a 6-foot-5, 200-pound sidearm specialist, features a two-seam fastball (88-91 mph), slider, curveball and changeup in his repertoire.
The scouting report passed around the Pacific Coast League in regards to Rapada also notes that the 26-year-old has a nice pickoff move. But top New York Mets prospect Carlos Gomez was a little late in picking up on that.
In the ninth inning of Iowa's 6-5 win over New Orleans last Saturday, Rapada gunned down the speedy five-tool Gomez at first base to end the game and secure the victory for his team.
"It was kind of a shock to see him get that big of a lead on me," Rapada had said after the game. "Given what I know from other teams, I have a pretty nice move."
And since he went back to basics, Rapada's sinking fastball has been a crucial key to his success, he says.
"It's been great these past few outings," Rapada noted. "Any time I've fallen behind in the count, I've been able to go back to it and let the sink get the hitters out."
For the time being, Rapada isn't thinking about when he might get another crack at Chicago's bullpen. His only focus now is to keep building his confidence. And keep turning those same old tricks.
"Any time you can rack a few good outings together, it's going to build your confidence and help you tremendously," Rapada said.