So, what exactly can Big Orange County expect to see once O'Brien straps on the Power T?
Allen Trieu, who is Scout.com's Midwest Regional Manager has seen O'Brien in action "a lot" in the camp circuit over the summers. He has also seen the 6-foot-3, 284-pounder's game film from three contest this season.
"He's been described by a lot of people who have seen him play as a bulldog," Trieu told InsideTennessee.com. "That's a good starting point with him because he plays tough, hard. He's a scrapper. He's a kid who plays with a lot of intensity. He's a mean kid on the field.
"I think sometimes when you say 'scrappy' it implies that that's all the guy's got, he's not really an athlete, but Danny's a good athlete for the size that he is. Really good interior lateral agility and quickness. He's got a great spin move, which I've seen him use to beat kids over and over again. I think they're going to get a high-effort, high-motor guy that can disrupt things and get into the backfield."
Through its 3-5 start, Tennessee is allowing opponents to a net of 4.3 yards per carry. It also has totaled just 13 sacks and three interceptions. Help tying up a pair of blockers in the trenches and a DT with some pass-rush skills could be quite beneficial in the future. How long it will take O'Brien to start tormenting Southeastern Conference offensive centers and guards remains to be seen.
"He's not ever going to carry 330 pounds, but I think he's going to be a guy you can plug in there and he's going to get the job done. He's very reliable," Trieu said.
"I see him as a pretty traditional nose, defensive tackle."
While the on-field product is struggling while dealing with injuries to key players and youth at a number of positions — six true freshmen starters against South Carolina — the coaching staff at Tennessee is still taking on some big-time competition in the recruiting world. And, in O'Brien's case, winning.
"Tennessee has felt like home to me every time I've been through there," he said the day he committed. "That was always the biggest thing for me in the recruiting process."
The Fenton, Mich., native had 16 scholarship offers from BCS schools, including the likes of Alabama, Florida, Michigan and Michigan State. He visited numerous schools besides Tennessee, including Alabama, Iowa, Ohio State and Vanderbilt.
"I think it's a great recruiting job," Trieu said. "He had offers from Michigan and Michigan State, who are right there in his back yard. Not only beating them, but he had an Alabama offer, a Florida offer. So, they're beating other SEC teams for him too. That was the same case with DeAnthony Arnett; he had offers from a lot of the same schools.
"So, I think for them to come here twice and do that is an outstanding recruiting job by the coaching staff. Maybe Danny will have the same freshman year impact that DeAnthony's having right now."
Arnett was the eighth-ranked wide receiver in the country and a four-star prospect coming out of Saginaw (Mich.) High School. The Vol freshman is tied for third on the team with 17 receptions for 167 yards and two touchdowns.
"DeAnthony said that the reason that he committed and went away is the same reason I committed," O'Brien said. "That kind of opened my eyes a little bit. He felt at home there. He felt a bond with the coaches. He got the same feeling I did when he took his visits."
O'Brien, who is already getting to know current UT players Austin Johnson and Jacob Storey, originally met Arnett through basketball.
O'Brien plays for Luke M. Powers Catholic High School, which opened the season losing three out of their first four games. However, the Chargers appear to be getting hot at the right time as winners of four straight, including a 35-13 postseason victory over visiting Frankenmuth last Friday.
The Chargers put their season on the line again in the second round of the MHSAA Div. VI state playoffs when they face Millington on Friday night at 7.
O'Brien officially visited the Tennessee campus in Knoxville back in mid-October. He shared his thoughts on how that went with InsideTennessee shortly before heading home that weekend.