The only other time Castro led off for the Cubs was last Aug. 8 against the Reds. In three games this year, Castro is 8-for-13 and has scored four runs. He's the first Cubs player to hit two triples in a game since Mike Fontenot did so May 29, 2010, against the Cardinals.
Quade talked to both Castro and hitting coach Rudy Jaramillo before making the switch. Kosuke Fukudome led off Friday, and Jeff Baker played the role Saturday.
"I want [Castro] to change nothing," Quade said prior to Sunday's game. "I think he understands that. I'm asking him to lead off today. He'll be back in the two-hole tomorrow almost for certain. We don't have a prototypical leadoff guy, and when [Fukudome's] in the lineup, he's our best guy. He's the best on-base percentage guy since we arrived here.
"This is about how good Starlin's become and the mix of the players I have in the lineup today."
Where Castro eventually ends up in the lineup is still to be determined. There was talk that he could bat third someday.
"He's got the ability to be a real special player both offensively and defensively," Quade said. "If he reaches his potential, why not in the three-hole one day?"
Castro, who turned 21 on March 24, is still developing as a player and a person. He's worked daily with infield coach Ivan DeJesus on his footwork, and his throws have been better this season.
"I think he's grown up leaps and bounds since last year," Quade said of the youngster, who batted .300 last season, his rookie year.
"Since Day One, since he showed up at Spring Training, we had a rough couple of days to start the games, but his work habits have been great," Quade said. "Growing up is a lot more than performance. He's maturing in a hurry."
Castro has impressed his new teammates.
"Unbelievable," Carlos Pena said. "The sky's the limit for a kid like that. I love his makeup, the way he thinks. He's way beyond his years. He's very mature, very humble and has a very bright future."
How far has Castro come? After Sunday's game, DeJesus was present to act as interpreter but was needed only to clarify the questions. Castro answered in English.
"I feel more comfortable because right now, I'm a rookie, but now people and players don't see me as a rookie," he said. "I have a little more respect because I have a little more experience. I feel really good."
And that's how he's playing, too.
"Any place you put him, he looks good, because he has so much talent," Alfonso Soriano said. "He can bat leadoff, second, third -- any place you put him, he'll do his job because he has so much talent."