Lambert could be called up for his major-league debut sometime this week, Thomas Harding of MLB.com reports.
Lambert looked good at big-league spring training this year but hasn't carried that success into the minor-league season. The 22-year-old has a 5.07 ERA, 1.58 WHIP and 51:16 K:BB through 60.1 innings at Triple-A Albuquerque.