The left-hander was 2-1 with a 6.23 ERA in 30 1/3 innings with Tennessee. He made his Triple-A debut on Saturday, tossing one scoreless inning.
The 25-year-old Schappert signed as a non-drafted free agent from Southwest Texas State University in 2004.
Sunday, Iowa added another pitcher to its bullpen when RHP Jim Henderson was promoted to Triple-A. Henderson made 18 appearances in relief at Tennessee and was 3-1 with a 0.75 ERA in 24 innings.
The Cubs acquired the 24-year-old Henderson from Washington in the minor league phase of the Rule Five Draft last December.
To accomodate the moves, Matt Avery was promoted to Tennessee from Class High-A Daytona. In 19 appearances, the right-hander was 1-1 with a 1.61 ERA in 22 1/3 innings. He was 7-for-9 in save chances.
The 23-year-old Avery was the Cubs' ninth-round selection in the 2005 draft from the University of Virginia.
Also promoted to Tennessee was RHP Grant Johnson. The 24-year-old was 1-1 with a 3.57 ERA in 16 relief appearances at Daytona.
The 25-year-old Shaver made three starts for Peoria after beginning the year in Extended Spring Training following minor off-season surgery on his left elbow to remove bone spurs. He allowed three runs (two earned) in 13 2/3 innings with Peoria for a 1.32 ERA.
In 19 appearances with the Chiefs, the 24-year-old Roquet boasted a 0.36 ERA in 25 innings. He was 11-for-11 in save chances and did not allow a run in his first 16 appearances with the team this season.
To coincide with the moves, RHP Miguel Cuevas-Novas was added to the Peoria roster. Cuevas-Novas, listed at 6-foot-9, 265 pounds, made his professional debut with the Mesa Cubs of the Arizona Rookie League a season ago and allowed six earned runs in 17 innings for a 3.18 ERA.