Sullivan agreed to a one-year, major-league contract with the Brewers on Monday, Robert Murray of FanSided.com reports.
The news of a major-league deal comes as something of a surprise, as Sullivan is a 27-year-old with zero major-league experience. He wasn't particularly good at the Triple-A level last season, either, hitting .223/.302/.375 across 90 games, but the Brewers evidently feel he adds something as an extra catcher who can also provide cover at the infield and outfield corners.