(Updated: Tuesday 11:30 a.m.)OWINGS MILLS, Md. — Turning their attention toward their annual trip to western Pennsylvania, the Ravens hope to welcome at least a couple key players back to the field against Pittsburgh in Week 4.Starting inside linebacker C.J. Mosley and top reserve defensive lineman Michael Pierce missed Sunday’s game against Denver, but head coach John Harbaugh said both were “really close” to being able to play in the 27-14 win over the Broncos. Mosley sustained a bone bruise in his left knee in the Week 2 loss at Cincinnati while Pierce missed the first game of his career with a foot injury.“They just didn’t make it this week,” Harbaugh said. “Still, you have to say it’s ‘day-to-day’ because you don’t know. But I’m really hopeful.”Rookie tight end Hayden Hurst and third-year defensive tackle Willie Henry have been sidelined since last month, but their return to the practice field could be just around the corner. Hurst had a screw inserted in his foot on Aug. 24 to help heal a stress fracture while Henry underwent surgery for an umbilical hernia around the same time. The Ravens would certainly like to add Hurst, their first-round pick, to an improved aerial attack that entered Monday ranked ninth in the NFL in passing yards per game. Henry appeared on the verge of securing a starting role along the defensive line during the preseason.“We’ll see. I don’t know yet,” said Harbaugh about the possibility of the two practicing this week. “There’s probably a better chance for Hayden. Willie is going to see a doctor here this week. It’s a little different with Willie because it’s not an orthopedic deal. The doctor — internist — has to clear him on that kind of stuff.”After working out a number of free-agent offensive linemen two weeks ago, the Ravens signed former Chicago center Hroniss Grasu to their 53-man roster on Monday. A 2015 third-round pick out of Oregon, Grasu made four starts and appeared in six games for the Bears last season and has started 12 games in his career. He was waived by Chicago at the end of the preseason and gives Baltimore a third reserve offensive linemen again after 2017 fifth-round pick Jermaine Eluemunor was waived over the weekend.To make room on the active roster, the Ravens waived defensive back Robertson Daniel, who had just been promoted as an extra healthy body after rookie cornerback Anthony Averett suffered a hamstring injury late last week.Harbaugh labeled new return specialist Tim White’s debut as “very solid” despite the rainy conditions, complimenting his ball security and decision-making with the Ravens holding a second-half lead. Baltimore waived returner Janarion Grant on Saturday after the rookie had fumbled a punt in each of the first two games.“We’re very hopeful that we’ll get him back on the practice squad,” Harbaugh said on Monday. “I really think those guys were a tossup anyway. Janarion did a good job, a couple balls on the ground. That’s part of it probably, and he knows that. No way do I think he’s not going to be a really good player. He’s going to play certainly this year.“But Tim was doing such a good job in practice. He’s been around, he’s more of a veteran guy, and we just felt that he should get a chance.”Both Grant and Eluemunor cleared waivers and were re-signed to the practice squad on Tuesday morning.