Speaking to reporters three days after suffering the injury, Witten remained hopeful that he will not need surgery, which indefinitely would sideline the seven-time Pro Bowler.
An operation is a possibility depending on how Witten fares in an examination in a week to 10 days, when the Cowboys return to Dallas.
"Initially when they said we need to talk about it, I was a little worried of how long it could be," Witten said Thursday. "Obviously being hopeful to not having to have surgery, I thought sooner than later. That's a positive sign. Yeah, I was concerned, but ultimately we got good news from that standpoint."
Witten's status still is uncertain for the Cowboys' regular-season opener on Sept. 5 against the New York Giants.
Per doctor's orders, Witten must remain idle to help the laceration close. He has been a spectator at the Cowboys' walk-throughs the past two days and will travel with the team to San Diego on Friday.
Witten went to the hospital on Tuesday after experiencing continued soreness from a first-quarter hit by Oakland Raiders linebacker Rolando McClain in Monday's preseason opener. His initial reaction to being told he had a spleen injury was typical Witten.
"Well, it was 'How long?'" Witten said. "Again, I do think it's a different mindset thinking you have to get healed up and regroup. Like [trainers] have said, just take it a day at a time. Obviously, I'd be hard-pressed to imagine not being out there against the Giants. But there's no timetable right now."
Witten has missed only one game in his career because of a fractured jaw as a rookie in 2003, and has played through a broken rib, knee and ankle injuries.
"It's different," Witten said. "It's not something you can just fight through and dig deep. But it's hard. It's the first time for me to be in this situation. I'm staying optimistic and staying positive. We're all hopeful to get the results we're looking for."
Witten described the pain level as similar to the broken rib, but it has lessened some the past few days to allow him to get around the team's training camp facility. He said the hardest part is doing nothing.
"Thinking about sitting in that hotel when the team is working, it's a challenge," Witten said. "Ultimately, it's the best thing you can do for the team. We've got plenty of guys to pick up the slack. That's not a concern. For me, I think it's just get healthy as quickly as you can. We'll regroup when we get back to Dallas."