The Cubs would not confirm reports Sunday night that first baseman Anthony Rizzo and the team had agreed on a seven-year, $41 million contract extension.
However, sources say an official announcement could come as early as Monday, when the Cubs return to Wrigley Field from Washington to open a series with the Colorado Rockies.
Ken Rosenthal of Fox Sports first reported the deal, which is said to run from 2013-19.
The 23-year-old first baseman is a cornerstone around whom the Cubs are building for the future. They obtained him on Jan. 6, 2012, in a trade with San Diego that sent pitcher Andrew Cashner to the San Diego Padres.
Rizzo spent the first part of the 2012 season at Class AAA Iowa before coming to the Cubs in late June. He batted .285 with 15 home runs and 48 RBI for the Cubs last season after his call-up.
This season Rizzo has a hitting line of .280/.352/.538 with 9 home runs and 28 RBI.