The Reds outrighted Johnson to Triple-A Louisville on Thursday, Charlie Goldsmith of Fox 19 Now Cincinnati reports.
Williamson (5-5) took the loss Sunday against Toronto, striking out three while allowing four runs on four hits and three walks in three innings.
Tolman earned the save in Sunday's 6-4 win over the Mets, allowing a walk and one hit while striking out two over 1.1 innings.
Chaparro went 3-for-4 with a pair of solo home runs in Sunday's 6-4 win over the Mets.
Gray earned the save in Friday's 7-6 win over the Mets, when he issued a walk and struck out a batter in the ninth inning.
Crews went 1-for-3 with a solo home run, two steals and two additional runs scored during the Nationals' 7-6 win over the Mets on Friday.
Alvarez did not factor into the decision Friday against the Mets, allowing five runs on seven hits and three walks while striking out seven across 4.2 innings.
De La Cruz went 1-for-4 with a two-run double and a steal during the Reds' 6-5 loss to the Blue Jays on Friday.
Lodolo did not factor into the decision Friday against the Blue Jays, allowing two runs on seven hits and two walks while striking out three across five innings.
Early (elbow) will be activated from the 60-day injured list and make his Nationals debut with a start Saturday versus the Mets, Mark Zuckerman of NatsJournal.com reports.
