WATFORD, England Lawrence Okoye can tell you Justin Smith's weight, where Ray McDonald went to high school, when Glenn Dorsey will celebrate his birthday.
Though that kind of knowledge has earned him ribbing from his 49ers teammates, it's an indication of how deeply the Englishman, who went through his first American football practice in May, has immersed himself in the sport.
"He's a football nerd right now," defensive-line coach Jim Tomsula said of Okoye on Wednesday as the 49ers prepared for Sunday's game against Jacksonville at Wembley Stadium. "It's all football. He talks it. He eats it. He sleeps it. The guys get on him because he can tell you where everybody's from. He can tell you what school they went to, what high school they went to, how tall they were in the ninth grade, how tall they are now."
Okoye injured his knee in the 49ers' third preseason game, and the team shortly thereafter placed him on injured reserve, ending his season. He can't practice, but he's permitted to rehabilitate alongside teammates, attend meetings and, mostly, study the game.
"I watch several hours of film a week, and I understand what's going on," he said. "I'm learning certain things, and things that didn't click before click now."
And his knowledge of minute NFL details extends beyond the 49ers' roster.
Before the draft, Okoye expressed admiration for Houston defensive lineman J.J. Watt, the league's reigning defensive MVP, who is similar in size to the 6-foot-6 Okoye. Asked if he's noticed other tall defensive players perhaps Arizona's Calais Campbell in the six months since, Okoye had a precise answer.
"He's slightly taller he's 6-8," Okoye said. "He's got the Margus Hunt type of size."
Campbell and Cincinnati's Hunt are listed as 6-8.
Okoye said he has a better understanding of how defensive linemen play and what makes the good ones effective. Perhaps the best at his job, he said, is Smith, who had far fewer sacks than Watt last year three vs. 20 1/2 but whom teammates elected as one of their captains for 2013.
"I can see the game better (now); I can see all the good stuff he can do," Okoye said of Smith. "He's not just a pass rusher. He affects the game in as many, if not more, ways than J.J. Watt does."
The 49ers gave Okoye a chance as an undrafted free agent not only because of his size and athleticism but because he's proven he can master a sport quickly. He took up the shot put when he was 18; at 20, he represented Great Britain last year in the London Olympics.
Okoye said training camp was "the hardest thing I could have gone through" and that playing against left tackle Joe Staley and guard Mike Iupati this summer "was a nice rude awakening."
Okoye said he can't wait to show those guys how much he's learned something that may not happen until the next training camp in late July.
Until then, Okoye is proving his worth in other ways.
The South London native has been especially popular this week with teammates who are eager to see the city.
"They think I'm the Yellow Pages," he said with a smile. "I just point them in the right direction."