For the third straight season, Fukudome began well, batting .344 in April, but he hit .253 in May and was 5-for-27 (.185) this month.
"He doesn't look bad at all," said Sasaki, who watched Fukudome during an early batting-practice session at Wrigley Field on Tuesday.
Sasaki will be in Chicago for 10 days, and it will give him and Fukudome a chance to do some extra work in the batting cage. The two spent time together this offseason and again in Spring Training. Fukudome was not in Tuesday's lineup against the Oakland Athletics, replaced by rookie Tyler Colvin in right field.
"We're giving 'Fuke' a little time off," Cubs manager Lou Piniella said Tuesday. "He's been struggling a little bit. With the hitting coach coming in, we'll give him a chance to work with him. It gives me a chance to play Colvin, too. We'll see what happens in the next few days."
It's been difficult for Piniella to give the five outfielders enough playing time.
"I would like to play everybody," Piniella said. "I've said it's difficult, and right now, we're going to play Colvin. [Wednesday], there's a real tough lefty, so we'll see what we do there. Right now, we'll play Colvin a little and let Fukudome get a breather, and at the same time, let him work with his hitting coach."
Sasaki, who managed former Cubs outfielder Tuffy Rhodes in Japan, said one of the things he noticed Tuesday was that Fukudome's timing was a little slow. Cubs hitting coach Rudy Jaramillo told Sasaki the same thing.
With the emergence of Colvin, who was hitting .296, Fukudome's name has been mentioned in trade rumors. The outfielder does have a limited no-trade clause in which there are 15 teams on his no-trade list. He's also owed slightly less than $8 million for the rest of this season and $13.5 million for 2011, which will limit teams' interest unless the Cubs were willing to pick up part of his salary.