"Jeff has done it before," Renteria said. "He's put in a very strong year, as [Travis] Wood did. The decision was quite easy for all of us."
Samardzija was the Opening Day starter last season and beat the Pirates 3-1, throwing eight shutout innings. But Wood had the better year and was the team's lone All-Star.
"It's nice to have it done with and out of the way," Samardzija said. "Now you can really set your schedule which is nice."
Renteria was asked if he needed to talk with Wood about the decision.
"I think you just have your conversations with your guys," he said.
It could be Samardzija's last Opening Day with the Cubs. He is set to become a free agent after the 2015 season, and sources familiar with the situation indicate the Cubs will trade him before then if they can't sign him to a long-term deal.
"We'll keep our fingers crossed that the snow is gone by then," Samardzija said.