PITTSBURGH -- Four trades and the acquisition of a former Pro-Bowl cornerback the week before the regular season is not a routine script for the usually reserved Pittsburgh Steelers.

This is not a routine year, though.

With no guarantees that Ben Roethlisberger or Le'Veon Bell will be Steelers beyond this season, Pittsburgh is trying to fix any weakness on the roster to keep a championship window cracked open.

Acquiring tight end Vance McDonald, cornerback Joe Haden and safety J.J. Wilcox won't exactly scare the New England Patriots. But the Steelers got better this week. And they exhausted all options with expendable players Ross Cockrell and Sammie Coates, getting late-round draft capital in return.

Consider this six-day flurry...Steelers gave up fourth- and sixth-round picks in 2018, Cockrell/Coates, a 2019 seventh-round pick and two backups; They added Haden/McDonald/Wilcox and four picks between rounds 5-7 from 2018-19.

To be sure, the Steelers are covering their own mistakes with these moves. At tight end, last year's Ladarius Green signing was one of the franchise's worst free-agency moves in recent history. The Steelers targeted tight ends on Day 3 of April's draft but didn't commit to one.

Their cornerback evaluations have garnered, at best, mixed reviews. Save Artie Burns, the Steelers have failed to develop a young cornerback that looks like a serious playmaker. That the franchise hasn't had a Pro Bowler at corner since the mid-'90s is a problem, and that's on them to find the right guys.

That's why it's hard to knock the Haden move, even with a $7 million price tag in 2017. He's an upgrade at outside corner. If he's 65 percent of the 2014 Haden, the Steelers got stronger on the outside.

The New York Giants acquired corner Ross Cockrell from the Steelers and envision him as a fourth cornerback. Apparently the Steelers did, too, and that's why they continued to make moves. A cornerback rotation of Burns, Haden, Coty Sensabaugh, William Gay, Mike Hilton, Cam Sutton (possibly to IR) and Brian Allen is an intriguing mix of talent, inexperience and aging veterans who might be slowing but can still play. I have no idea how this will all work, but at least the Steelers have more options to mix up coverages.

The Wilcox trade with the Tampa Bay Bucs is insurance in case Mike Mitchell and Sean Davis miss time, but it's more than that. It's a statement that the backup safeties in place weren't good enough, and against the league's top quarterbacks, at least four capable corners and three capable safeties is essential.

Mitchell, who's missed the last month with a lower-body injury, wants to play Week 1 in Cleveland but might need more time. Wilcox is a plug-and-play safety who's eager to show he's more than a run-stopper.

The Steelers have no excuses for missing the playoffs and aren't going to make any if they do. This week reaffirms that.