But Kruger was the diligent understudy despite being inactive for seven of the first 11 games, learning his lines in case he was needed. Radio sports-talk callers and the Internet blogs and message boards clamored for Kruger to make an appearance, especially when Suggs was injured two weeks ago.
Kruger stepped into the spotlight Sunday night at M&T Bank Stadium. He picked off a pass from Pittsburgh Steelers quarterback Dennis Dixon and ran it back 26 yards, leading to Billy Cundiff's 29-yard field goal and a 20-17 Ravens win in overtime against their AFC rivals.
Even standing at center stage, Kruger downplayed his rave reviews.
"It was a designed blitz," Kruger said of his pick. "They were coming from the other side. I was the dropper [in the passing lane].
"I just happened to be at the right place at the right time. My teammates did a great job getting there. It was a great call, obviously. So it was a number of things."
But Kruger's teammates seemed to feel he was far too modest in describing his interception, as well as the role he has played in filling in lately for Suggs.
"It was just an unbelievable play," linebacker Jarret Johnson said. "It wasn't an easy catch. To get out and make a catch like that shows unbelievable athleticism."
Said middle linebacker Ray Lewis: "It just doesn't get any better than that. You have a young man who is just patiently waiting his turn. Can you replace a Terrell Suggs? No, unless you're replacing him with Paul Kruger. For him to come in the game at that crucial situation and to make a play that big, it shows what it means about 'next man up' around here.
"I've been praising Kruger for a long time. It was just his time."
But the long wait for that moment of glory was killing Kruger, 23. The Ravens signed him to a four-year, $3.25 million contract in July. Yet he was on the inactive list for the Ravens' first three games, against the Kansas City Chiefs, San Diego Chargers and Cleveland Browns, then played only sparingly against the New England Patriots.
He was then inactive for the Cincinnati Bengals, Minnesota Vikings and Denver Broncos games, as well as the rematch with the Bengals, before rotating into the defensive lineup the past three games against the Browns, Indianapolis Colts and Steelers.
"It's been hard all season," Kruger said of having to watch from the sideline. "I'm a competitive guy. I want to be on the field, but I respect the coaches' decision."
The Ravens' coaches said the lack of playing time was no reflection on his talent or work ethic. They said it was simply a matter of who was ahead of him on the depth chart and the defensive schemes the team was using each Sunday.
Kruger said coach John Harbaugh even approached him a few days before the Steelers game to offer encouragement.
"Just keep fighting. Keep going in practice," Kruger said Harbaugh told him. "Work hard and when I'm in there in a game, make the best of every opportunity I can."
But it was the injury to Suggs, who suffered a severe ligament sprain in his right knee from an illegal chop block by Browns quarterback Brady Quinn in the Ravens 16-0 win Nov. 16 that significantly increased Kruger's playing time.
"It's tough, especially when you're a rookie and you're behind a player like Terrell Suggs," Johnson said of Kruger's place on the depth chart. "You're a high draft pick and all that stuff. You just tell him: 'Be consistent. Focus every day.'
"You gotta use those [practice days] to get better and he's done that. The guy's done nothing but improve."
Johnson said he and other Ravens sensed Kruger's frustration from time to time during the season.
"Oh, sure, it's natural," Johnson said. "But he's kept his cool and not really said anything. I've only been down one day and I almost lost my freaking head. I almost went nuts.
"And for him to come into the situation he's been in, just numbers-wise, and there's not a whole lot he can do and just to stay as cool as he is and get better every day, that's huge."
So was the interception against the Steelers, which Kruger hopes was a sign of big things to come.
"I want to be out there," he said. "I wanted to work hard and do well in games to give Baltimore City the best team we can. So I hope it's a starting point."