"It's a costly loss," Cubs manager Lou Piniella said. "It's a bad break for us, it really is."
Soriano suffered a minimally displaced fracture of the fourth metacarpal on his left hand when he was hit by a pitch by Atlanta's Jeff Bennett in the second inning of the Cubs' 7-2 victory Wednesday night.
"You never want one of your guys to go down, no matter who it is," Ryan Theriot said. "Guys are just going to have to pick up the slack, and I think we're going to be fine."
X-rays revealed the break, and Soriano's finger will be in a splint for three weeks. Team officials said they will have a better idea after that as to when he can return. However, he is expected to be sidelined a minimum of six weeks.
With a runner on base and two outs in the Chicago second, Soriano was struck by the third pitch from Bennett, and the ball appeared to ricochet off the outfielder's face. Soriano fell to the ground in obvious pain, but walked off the field under his own power, accompanied by Cubs athletic trainer Mark O'Neal.
"It's unfortunate," Chicago's Derrek Lee said. "I feel bad for him. He was injured before, and he worked hard to get back, and now he has a freak accident like this. I feel bad for him. The guy wants to play and he likes being on the field. I've been through it, and it's not fun. I feel for him."
Soriano, who was the leading vote-getter among National League outfielders in the All-Star balloting, was batting .283. He hit his team-leading 15th home run on Saturday, and was hitting .323 with 13 homers and 35 RBIs in his past 38 games since returning from the disabled list.
The Cubs did not feel Soriano was hit intentionally.
"He stands right on top of the dish," Chicago pitcher Ryan Dempster said. "He's a tough presence there. If you're going to go in, you better get it in, because if not, it'll end up on Waveland [Avenue]. He unfortunately missed, and it hit him in a bad spot."
This will be the second time this season that Soriano will have to go on the DL. Soriano was sidelined from April 16-May 1 because of a strained right calf.
"He looked like he was really getting going," Theriot said. "It wasn't anything to do with his legs, so when he comes back, you can count on that to be there, too."
Many of the Cubs players cringed when the ball hit Soriano's hand.
"There's so many small bones in your hand, it doesn't take a whole lot for something to go wrong in there," Chicago's Reed Johnson said. "When you've been around baseball, any time a guy takes something in his hands, you're concerned. We got some bad news today."
The team was expected to call up outfielder Micah Hoffpauir from Triple-A Iowa to take Soriano's spot on the roster, and will likely add another player this weekend for the Interleague series in Toronto, rather than continue to carry 13 pitchers.
"We'll probably have to get two kids up here now," Piniella said. "It's a shame, it really is [about Soriano]."
Who will lead off is another matter to be resolved. Johnson was the leadoff man for 12 games when Soriano was hurt, and the Cubs went 8-4.
"I'll play anywhere," Johnson said. "Everybody knows that's a comfortable spot for me in the order. I've been hitting eighth a lot, which is becoming a little more comfortable for me. Wherever I play shouldn't change my approach."
Theriot also stepped into the No. 1 spot, and the Cubs were 0-3. Theriot has done well batting second lately.
"Don't count on me to start hitting leadoff homers," Theriot said.
The loss of Soriano put a damper on Dempster's complete-game victory Wednesday night.
"We've got a strong team here," Dempster said. "That's been the thing that's been to me the most noticeable is when guys have been asked to play, they've done such a good job. That's the luxury you have when you have a guy like Reed Johnson sitting on your bench and Mark DeRosa, who can go play left field. It shows the depth of our team. Now we've got to go out there and keep playing well and wait for him to get back."
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.