BOSTON -- Celtics big man Al Horford said he plans to travel with the team on a two-game road trip that starts Saturday night in Indiana with hopes of returning to game action after being sidelined for nearly two weeks due to a concussion.Horford, who has slowly navigated the NBAs return-to-action protocol, missed his fourth straight game with Fridays visit from the New York Knicks. He engaged in an individual workout before Fridays game and is encouraged by his recent progress.Ive been banged in the head before, but nothing like this, said Horford, who was reluctant to get into the specifics of the injury or his recovery.Im getting better each day and the past two days have been really good for me. I was able to get on the court a lot more and run up and down. Do a lot of movement, a lot of stuff I wasnt able to do a couple of days ago.The Celtics had lost all three games without Horford entering Fridays tilt with the Knicks and have been a mess defensively.Its been difficult [to watch] just because you want to be out there helping your teammates, fighting every night, Horford said. Its tested my patience this time. Everyone here has been very supportive, starting with coach [Brad Stevens]. Just down the line all the guys. But Im just very encouraged by my work today. I feel like Im in pretty good shape.Stevens said that Horford would only travel if he had the potential to play on the trip. The Celtics visit the Pacers on Saturday night, then play in New Orleans on Monday. The Celtics have urged Horford to be patient in his recovery.I dont want to even act like Im a doctor but, from what I understand, each concussion is unique, Stevens said. It was diagnosed as a mild concussion but as long as there are symptoms that reoccur then that continues the protocol. And thats good. Im thankful Im coaching in an era where thats the case. The most important thing is that his health is prioritized. And mild or not, a concussions a concussion.The 30-year-old Horford, who signed a four-year, $113 million deal with the Celtics this offseason, said he was now operating with an awareness that head injuries are much different than typical bumps and bruises.I honestly didnt understand it before now, Horfor