The 19 first-round winners are joined by 25 entrants from the USL Championship.
A few games of note:
Eric Wynalda's Las Vegas Lights host Cal FC, the team he led to the quarterfinals in 2012. The USL Championship's Orange County SC places Orange County FC, coached by Paul Caligiuri.
Three meetings of USL Championship teams are on tap: Austin Bold-Tulsa Roughnecks, Phoenix Rising-New Mexico United and Sac Republic FC-Reno 1868.
Second Round, Schedule:
Tuesday, May 14
Charlotte Independence-Florida Soccer Soldiers 7 pm.
Tampa Bay Rowdies-The Villages SC 7 pm.
Pittsburgh Riverhounds-Dayton Dutch Lions 7 pm.
Hartford Athletic-New York Cosmos B 7:30 pm.
Nashville SC-South Georgia Tormenta FC 2 8:30 pm.
OKC Energy FC-NTX Rayados 8:30 pm.
Austin Bold-Tulsa Roughnecks 8:30 pm.
San Antonio FC-Laredo Heat 8:30 pm.
Las Vegas Lights-Cal FC 10:30 pm.
Wednesday, May 15
El Farolito-Fresno FC 5:30 pm.
North Carolina FC-Richmond Kickers 7 pm.
Greenville Triumph-Charleston Battery 7 pm.
Indy Eleven-Lansing Ignite FC 7 pm.
Louisville City FC-Reading United AC 7 pm.
Birmingham Legion-West Chester United 8 pm.
Memphis 901 FC-New York Red Bulls U23 8 pm.
Des Moines Menace-Saint Louis FC 8:30 pm.
El Paso Locomotive-Forward Madison FC 9 pm.
Colorado Springs Switchbacks-FC Denver 9 pm.
Phoenix Rising-New Mexico United 10:30 pm.
Orange County SC-Orange County FC 10:30 pm.
Sac Republic FC-Reno 1868 FC:30 pm.