Shaw (back) started for Triple-A Iowa on Wednesday and Thursday and went 2-for-9 with an RBI between the two contests.

Shaw strained his back making a play in the field Sunday for Triple-A Iowa and is considered day-to-day, MLB.com reports.

Shaw has hit safely in 12 of the last 13 games for Double-A Tennessee, batting .460 (23-for-50) over that stretch with four homers, five steals, 12 RBI, 16 runs and a 3:3 BB:K.

Shaw is hitting .204 with a .354 OBP, three home runs and eight steals in 31 games for Double-A Tennessee.

The Cubs announced Friday that Shaw received an invitation to major-league spring training.

Shaw said Saturday that he's taken "probably 99 percent" of his reps this offseason at third base, Ryan Herrera of AllCHGO.com reports.

The Cubs promoted Shaw from High-A South Bend to Double-A Tennessee on Monday, Sahadev Sharma and Keith Law of The Athletic report.