MESA, Ariz. -- The waiting game in regards to Jose Contreras and Bartolo Colon breaking camp with the White Sox should come to an end Monday after the duo faces the Angels in Tempe, Ariz.

"I think so," said White Sox manager Ozzie Guillen when asked about making the call on the two starters early next week. "I don't think we can wait. We can't finalize this ballclub right now because of the decisions we have to make with Colon and Contreras. We have our hands tied up because we don't know what they are going to be able to do."

Colon will get the start against one of his former teams, followed by Contreras. With the two veteran hurlers scheduled to work the bulk of the contest, other pitchers set for that day such as Octavio Dotel, Randy Williams, D.J. Carrasco and Bobby Jenks might move to a Minor League game.

A significant step forward was made by Colon during his start this past Wednesday against the A's at Camelback Ranch-Glendale. The right-hander, recovering from October surgery to remove bone chips from his elbow, needed a mere 43 pitches to get through 4 1/3 scoreless innings. His velocity was up, his location was pinpoint and the White Sox left that outing with an extra boost of confidence in relation to his possibility for an April 11 start at home against the Twins.

But pitching coach Don Cooper wants to see more before Colon officially is named the team's fifth starter. The same holds true for Contreras, who yielded three runs on five hits over four innings against the A's. It's just that the expectations are slightly different, based on the pitchers' respective injuries.

"Definitely two different things," said Cooper of Colon and Contreras. "With Colon, we need him to climb pitch total-wise and we need to get one more inning. More importantly, everything was [improved] last time. His work in between, his pregame work and the game was a level up. I would love to see Bartolo climb another level before we leave and keep the command.

"With Contreras, it's not that much about stuff really. It's the command of that stuff. Both guys have those differences, but the similarity is that they both really are in their third week of Spring Training. So we need every outing to get that done."

If a decision can't be made following Monday, then Contreras and Colon are on the schedule for next Saturday's Cactus League finale against the Diamondbacks at Chase Field. Guillen stressed once again prior to Friday's game with the Cubs that he would like to get the full roster set as soon as possible, especially before the two-game series with Arizona.

Guillen's fourth and fifth starters have a major ripple effect on the remaining two or three open spots on the pitching staff. And according to Cooper, he has a positive feeling about the two entering Monday.

"I'm sitting here thinking now it's more favorable than not," said Cooper, rating the chances for Contreras and Colon to leave with the team. "[The appearances against Oakland] made it 70-30 in their favor. This next one could make it 80-20 or 90-10."