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Mashaba is one of at least 30,000 matriculants who have been queuing at the UJ Kingsway Campus in Auckland Park to apply for places.
On Monday he stood in the queue from 8am until 2pm. Yesterday he was there from 5am and was told at 11pm he could not be accepted.
Those queueing were late applicants, re-applicants and first-time walk-in applicants.
The university yesterday said about two-thirds of the late applicants flocking to its Bunting and Kingsway campuses might not get in at all.
UJ registrar Marie Muller said the number of late applications could be attributed to the greater number of matrics who obtained university admission in the 2010 exams.
Even if these students complied with the minimum requirements for their chosen field, they would not necessarily get in. "We have limited space," she said.
Those queuing outside were handed application forms and 100 late applicants were allowed on to campus at a time.
The university only has space for 13,000 first years and has already conditionally accepted 17,500 new students based on Grade 11 results during its pre-selection.
Many of these had applied at other universities as well and might not register later this month.
The UJ received 63,400 applications for first-year undergraduate studies in 2011 during the dedicated application period in 2010.
The University of the Witwatersrand is not experiencing high volumes of late applicants. Wits enrolment centre head Carol Crossley said there were about 200 students queueing at the institution, but many of these had been rejected last year and were trying their luck again.