Lamar Jackson is missing the first week of the Baltimore Ravens' organized team activities, marking the first time that the former NFL MVP quarterback hasn't been present at the voluntary spring workouts.

'We've been down this road many times through the years," Ravens coach John Harbaugh said after Wednesday's practice. "I'll just let Lamar speak for himself on that. It's for him to talk about. You can ask him."

Asked whether he's concerned about Jackson missing practice time, Harbaugh said, "It's not for me to speak for somebody else on that. It's up to him to speak for himself on that."

Jackson indicated on social media Tuesday that he wasn't in attendance for the start of OTAs, but he didn't provide a reason for his absence. He tweeted, "Can't wait to get back," with purple heart and rocket emojis.

Baltimore has eight remaining voluntary OTA practices through the middle of June. Jackson is obligated to attend only the team's mandatory minicamp, which is scheduled for June 14-16.

"If it was training camp, it'd be really bad," cornerback Marlon Humphrey said. "I think as long as guys are working, no matter where they are, that's the biggest key. I spoke with Lamar earlier in the offseason. He said he will be coming in soon."

Jackson is entering his fifth-year option, which will pay him $23.016 million this season. The Ravens are expected to place the franchise tag on him next offseason if the sides can't reach an extension.

"Voluntary does means voluntary," Ravens president Sashi Brown told WBAL Radio in Baltimore on Thursday. "Lamar's been out working this offseason ... so no, I don't think any reason for alarm.

"[Jackson's] been very vocal in terms of his support and desire to be in Baltimore. We're pleased that he's out there working and not going to make a big deal out of this."

Ravens tight end Mark Andrews said he has spoken to Jackson and knows how hard he's working away from the facility.

"He's extremely motivated and extremely hungry," Andrews said. "So there's no worries over there. I know what he's doing and we're all working and doing our job here and getting ready for him. We'll be ready to go and I'm confident that he's going to be ready and show everybody what he's got and the type of hunger he has right now."

Ravens general manager Eric DeCosta has repeatedly said the team has tried to engage in long-term contract negotiations, but Jackson hasn't been interested in doing so. When asked about contract talks with Jackson earlier this month, DeCosta said "nothing has really changed on that front."

Jackson has attempted to squash speculation that he is looking to leave Baltimore. In March, he tweeted that he loves the Ravens and cited a "false narrative" that he is considering leaving the franchise.

Jackson's absence comes at a time when Baltimore is looking to rebound from its first last-place finish in the AFC North in 15 years. He's familiar with the Ravens' offense after playing the past three seasons in offensive coordinator Greg Roman's system. But Baltimore has one of the youngest groups of wide receivers in the NFL. None of the 12 receivers is older than 25, and none has played more than two seasons in the NFL.

Ravens officials have praised Jackson's workouts away from the facility. Jackson has been throwing to wide receivers Rashod Bateman and James Proche during private sessions in Florida and California. He also has been training with throwing coach Adam Dedeaux.

"We are getting great reports," DeCosta said earlier this month. "We talk to him all the time. We check in with him all the time. We talk to other players. I believe -- and I think Coach [John Harbaugh] feels this way -- that we are poised to have a great year on offense."

Jackson is coming off the most challenging season of his four-year career. Last season, he threw a career-worst 13 interceptions and was sacked a career-high 38 times. He missed the last four games with a right ankle injury. Jackson's last full practice with the Ravens was Dec. 10.

The Ravens added depth at quarterback by signing Brett Hundley on Thursday. Hundley joins Tyler Huntley and undrafted rookie Anthony Brown as the only other quarterbacks on the Ravens' roster.

Hundley, 28, has played 18 games in his seven-year career, which has included stints with the Packers, Seahawks, Cardinals and Cowboys.