Baez, 19, began the year at Class A Peoria and batted .333 in 57 games before he was promoted in early August to Class A Daytona. He was batting .153 in 17 games there. Szczur, 23, a fifth-round pick in 2010, was in the Cubs' Major League Spring Training camp, and began the season at Daytona, where he hit .295 in 78 games. At Double-A Tennessee, he was batting .202 in 30 games.
They'll be joined on the Mesa Solar Sox team by infielder Rubi Silva and pitchers Dae-Eun Rhee, Nick Struck, Tony Zych, Zach Rosscup and Kevin Rhoderick. Rhoderick will be on the taxi squad.
The Arizona Fall League celebrates its 20th anniversary season this year. The six-team league, owned and operated by Major League Baseball, plays six days per week, Monday through Saturday, in six Cactus League stadiums, including HoHoKam Stadium in Mesa, Ariz.
Jorge Soler, who signed a nine-year, $30 million deal with the Cubs in late June, was expected to play in the Cubs' instructional league in Mesa this fall. Soler, 20, was batting .305 with two home runs and five doubles in 15 games with Class A Peoria.
"Jorge hasn't played much baseball," said Brandon Hyde, the Cubs' Minor League field coordinator who was promoted Wednesday to the club's director of player development. "We're excited about the start he's had in Peoria. He just hasn't played much and we want to get him in instructional league and get him five weeks to get this legs underneath him and get in playing shape. He was short on experience this last year. He's a special talent."
Silva, 23, a Cuban who signed with the Cubs in December 2010, hit .302 in 111 games at Daytona, and was batting .276 in 15 games at Tennessee.
Rhee and Struck were both starters at Tennessee, with Rhee, 23, posting a 9-8 record and 4.95 ERA in 26 games, while Struck was was 13-10 with a 3.30 ERA. Struck, 22, a 39th-round pick in 2009, threw a no-hitter at Class A Peoria in 2010, and has five quality starts in his last eight games.
Zych, 22, a fourth-round pick in 2011, was 2-1 with a 3.80 ERA in 18 games in relief, Rosscup, 24, had a 4.64 ERA in 10 games, and Rhoderick had a 4.87 ERA in 43 games. Rosscup was acquired from the Rays in the Matt Garza deal, and also pitched in three games for Class A Peoria.
Rhoderick, 24, was a ninth-round pick in 2010, and posted a 1.35 ERA in 21 games in the first half of the season. He has a 7.92 ERA in 22 games in the second half.