Earlier in the season, the Diamondbacks suspended Daron Sutton for wearing suits. Or something. So they were already an announcer down in the booth, and news broke on Friday that Mark Grace was going to take an indefinite leave of absence to "seek personal assistance." From the Arizona Republic, the mystery has been cleared up:

According to Scottsdale Police, Grace was pulled over at about 9 p.m. for having expired registration on his license plates. Grace was also arrested for DUI in Scottsdale on May 30, 2011.

This is Grace's second DUI arrest since joining the Diamondbacks' broadcast team -- he was also arrested in May, 2011.

Grace's former Diamondbacks teammate, All-Star Luis Gonzalez, will take over commentary duties on Friday and Saturday, and 86-year-old, Ford Frick award-winning, announcer Joe Garagiola will be on the broadcast for Sunday's game against the San Diego Padres.

Grace has been in the Diamondbacks' booth since 2004.