Kontos (0-1, 1.59 ERA) had complained of soreness off and on since spring training and had tests done on Monday, which revealed the problem.
In addition, righthander Chris Heston, who pitched a no-hitter against the New York Mets last year, was optioned to Triple-A Sacramento. He took the loss Monday night against the Diamondbacks in 11 innings.
Broadway appeared in 21 games with the Giants last year and had appeared in four games with the RiverCats. Okert is 1-0 with a 2.70 ERA in four games with Sacramento.