It was a difficult day in St. Louis Blues history: Alex Pietrangelo, captain and number-one defenseman of the Blues on their way to a Stanley Cup Championship in 2019 (where he scored the winning goal!), became an unrestricted free agent in the summer of 2020. He signed a seven-year contract with the Vegas Golden Knights worth $61.6 million, carrying a cap hit of $8.8-million annually and a full No-Move Clause.
That NMC is important: it was widely reported that Pietrangelo was unwilling to sign a contract that didn't include a full-NMC, because he wanted stability for himself and his young family. Armstrong refused to give it to him, and Vegas stepped up to give Pietrangelo what he wanted. Since joining the Knights, Pietrangelo continued to be one of the league's best defensemen and won a second Stanley Cup in 2023, though it appears his career may be over due to injuries, with two years remaining on his contract.
Losing Pietrangelo hit the Blues' defense corps hard, and Armstrong scrambled to find a solution--two solutions, in fact. Armstrong signed Torey Krug and Justin Faulk to matching seven-year, $45.5-million contracts that each carried cap hits of $6.5 million and included no-trade protections throughout: full No-Trade Clauses for the first five years, and Modified NTCs for the final two. Faulk and Krug never lived up to their contracts, with Krug's career likely over due to injury as well, and neither player could replace what Pietrangelo brought to the lineup.
It was a colossal fumble to let Pietrangelo walk over an NMC--trade protections Armstrong wound up giving to two lesser players to try and replace Pietrangelo; it was a total mismanagement of the cap and the beginning of a downward spiral the Blues are only just now pulling themselves out of.
What if the Blues had kept Pietrangelo, though? Re-signed him, and not made the blunder of handing out matching albatross contracts to both Krug and Faulk. On the one hand, the Blues likely would've remained a more competitive team through the early 2020s: even with the departures of Ryan O'Reilly and Vladimir Tarasenko, the Blues' forward group has remained strong as Jordan Kyrou and Robert Thomas have emerged as true top-line talents. With Pietrangelo on the backend, they would've had a rock-solid No. 1 defenseman and could've filled out the rest of the blue line in other ways. Would that have been a true Cup-contending team? Maybe not, but the 2018-19 team that did win didn't fit the mold, either.
On the other hand, keeping Pietrangelo would've just delayed the inevitable: the Blues' other core players were aging and approaching free agency, and continuing to "go for it" would likely have put a serious dent in the prospect pool as picks and young players were traded for deadline rentals and "win now" veterans. Instead of the (so far) successful retool that's turning the team around, we'd probably be in the early days of a far more painful rebuild--especially if Pietrangelo's career were to end the same way it appears to be in Vegas.
Would making Pietrangelo a Blue for life have given the Blues another shot at a Stanley Cup? Maybe, but it seems unlikely and would've just put off a rebuild for a few more years. Losing Pietrangelo for nothing, though--and trying to replace him by overpaying free agents--probably did far more long-term damage to the roster than his absence alone ever would have. Here's hoping the Blues have learned from that blunder when their current crop of stars reaches free agency.