Although he’s out of the lineup for a third straight with a stiff back, Alex Rios said he’s not concerned. Manager Robin Ventura is willing to go along with Rios so long as he’s back in the lineup on Wednesday. The White Sox outfielder headed to the doctor for an MRI on Monday morning but said because he has experienced the same pain before he knows what to expect. Rios injured the back in the weight room on Saturday morning but thinks he won’t be affected long term. “I don’t think so,” Rios said. “It’s a thing that’s going to take a few days. It’s going to have to wait it out. It will be fine. I’ve had this before in my career. It’s just a normal (stiffness).’” Rios hit .304 with 25 homers, 91 RBIs and stole 23 bases last season. Ventura has also tabbed him as the team’s No. 3 hitter to start the season. Although Rios has accrued plenty of at-bats between the World Baseball Classic and Cactus League, his manager would like him to get a few more reps between the April 1 season opener.