– Perhaps reaching the big 3-0 six days ago helped Greg Jennings, wise old philosopher, answer the most obvious Week 4 question when it comes to Greg Jennings, NFL receiver who no longer catches footballs from future Hall of Famers and is 0-3 for the first time ever.

The question: “How in the world do you handle the frustration of not playing with Brett Favre or Aaron Rodgers?”

“Frustration?” Jennings said with a laugh. “What frustration?”

C’mon, Greg.

“No,” he said. “I feel you. And it’s a challenge. It really is. But it teaches me to humble myself.”

Jennings was speaking not in Green Bay, Wis., his NFL home the past seven years, but Watford, England, an hour outside of London, where his Vikings were getting backup quarterback Matt Cassel ready to start in case Christian Ponder’s rib injury prevents him from facing the Steelers on Sunday at Wembley Stadium.

The last time a team Jennings played on changed starting quarterbacks was 2008. The Packers said goodbye to Favre in the spring, figuratively locked the door when he tried to come back in the summer and officially moved on with Rodgers in the fall.

In his career, Favre threw 10,169 passes and completed 62.0 percent of them. He won 186 games and threw 15 of his 508 regular-season touchdowns to Jennings.

Rodgers has thrown 2,787 passes with a 65.8 completion percentage and an NFL career-leading 104.9 passer rating. He has won 53 games and thrown 38 of his 179 TD passes to Jennings.

“In life, things aren’t perfect,” Jennings said. “But for my first seven years, they were pretty close. Especially at that position [quarterback].

“You learn not to take things for granted. But you also really focus on self-assessments. For me, if I see one of my teammates make a mistake, I automatically refer back to something I know I could have done better, so I don’t point fingers.”

Ponder has thrown only 874 career passes, but has completed only 59.2 percent of them. In 29 starts, he is 12-17 with 30 interceptions.

Cassel, who’s being hailed by fans as a potential savior of a lost season, was cast as villain only a year ago when the turnover-prone Chiefs went an NFL-worst 2-14. Cassel has thrown 2,044 passes with a 58.9 completion percentage. He’s 5-12 with 21 interceptions in his past 17 starts.

Vikings coach Leslie Frazier acknowledged Thursday that NFL receivers can be a challenge. He speaks from painful experience less than seven months after having to trade Percy Harvin because he and the Vikings could no longer coexist.

“[Jennings’] personality is one where he’s not the typical superstar [where] he wants it to be about him,” Frazier said. “A lot of wide receivers really like things to go through them. That can be a high-maintenance group. Greg is an ultimate team guy.”

Jennings has 436 career catches for 6,697 yards (15.4) and 53 touchdowns. Yet he finds himself with 11 catches on a run-oriented team that’s one of only two in the NFL — Jacksonville is the other — that doesn’t have a wide receiver with a touchdown reception.

Jennings, of course, isn’t perfect when it comes to selflessness. He admits to battling the urge to call for the ball more. One of those times came in this year’s season opener, when he caught three passes for 33 yards while Jerome Simpson was catching seven for 140.

In the week after the game, Jennings sat down with Frazier in his office.

“We were talking and he said, ‘There was a moment in the game where I was saying, man, I wouldn’t mind if I got this play called or that play called for myself,’ ” Frazier said. “He said, ‘I thought about it and said you know what, I’m happy for Jerome. This is good for our team. I want Jerome to have success, Kyle Rudolph. I want the whole team to have success.’ I’m like, that’s unique for a guy who has achieved what he’s achieved and signed a contract to come here.”

Jennings signed a five-year, $45 million deal that came with $17.8 million guaranteed in the first two years. So far at least, the $9 million-a-year receiver hasn’t acted like one has come to expect.

“Pride was one thing I saw myself struggling with in that Detroit game,” Jennings said. “Everyone says pride is good, pride is good. But pride is not good on a team. You want guys to be competitive. When you become prideful, you’re thinking about yourself and yourself only. … So, for me, yeah, I don’t think I’m the typical receiver.”