Second string and Small-time

Second string noun - A squad of players that are available either individually or as a team to relieve or replace the players who started the game.

Small-time and second string are semantically related. In some cases you can use "Small-time" instead an adjective phrase "Second string".

Small-time adjective - Of minor importance.

Second string and small-time are semantically related. Sometimes you can replace phrase "Second string" with "Small-time", this phrases are similar.