More evidence of the Chicago Cubs' extremely difficult season emerged Monday as they not only lost their best pitcher to injury for at least two weeks, they lost one of the best pitchers going in the game right now. Right-hander Ryan Dempster, who currently has a scoreless streak of 22 consecutive innings, was placed on the 15-day disabled list with tightness in his latissimus dorsi muscle. The Cubs recalled left-hander Scott Maine to take his place on the roster, with Randy Wells scheduled to take Dempster's spot in the rotation Wednesday against the White Sox.