Contreras (back) is starting at first base and batting second Friday against the Tigers, Chris Henrique of BostonSportsJournal.com reports.
Contreras' back tightened up on him Tuesday, and he was out of the lineup Wednesday against the Twins ahead of Thursday's off day. Contreras has been one of baseball's best hitters over the last couple weeks, as he's slashing .378/.500/.676 with three home runs, 10 RBI and eight runs scored over the last 15 days.