ESPN recently put together power rankings based on how each NFL team is positioned for these next three seasons. The Los Angeles Rams finished 28th. That is, um, not good. It's not good because, well, 28th is bad. It's really not good because of what the next three years represent for this franchise. Thanks to heavy rainfall in a city that never experiences heavy rainfall, these next three years now constitute the buildup to the Rams -- and Chargers -- moving into their vast, opulent $2.6 billion stadium in Inglewood, California.

The Rams -- 13 years removed from their last playoff appearance, 14 years removed from their last winning season -- want to become legitimate contenders as quickly as possible. More specifically, they want to ensure they are a playoff-caliber franchise by the time they move into that new stadium. ESPN's Louis Riddick, Mike Sando and Field Yates don't think they will be -- at least not as currently constructed. The trio graded each team's roster, quarterback, draft, coaches and front office, and crunched the numbers to come up with a final score. The result: 27 of the 31 other teams are, in their minds, better positioned for success from 2017 through 2019.

The Rams can't have that. They can't have a disinterested fan base in the nation's second-largest media market, and they can't play second fiddle to the Chargers in a stadium they themselves are funding. This week -- the last full week before training camp -- we're going to take a look at the five things that need to happen in order for the Rams to be a lot better than the 28th-best team at the conclusion of this three-year stretch.

No. 4: Keep the defensive core intact, starting with Aaron Donald.

Maligned as their drafts have been in recent years, the Rams have actually done a nice job building their defense.

What a shame it would be if that defense dissolved before their offense could even catch up.

Last year, the Rams lost their primary cornerback, Janoris Jenkins, and their starting free safety, Rodney McLeod, to free agency. This year, they lost their starting strong safety, T.J. McDonald, and had to use a second straight franchise tag just to ensure they didn't lose their new primary corner, Trumaine Johnson. Now, Johnson is one of 10 looming free agents from their defense. The list also includes inside linebacker Alec Ogletree, outside linebacker Connor Barwin, strong safety Maurice Alexander, defensive back Lamarcus Joyner, cornerbacks E.J. Gaines and Nickell Robey-Coleman, defensive ends Dominique Easley and Ethan Westbrooks, and safety Cody Davis.

Let's recap ...

Three cornerbacks -- including the No. 1 and two others in line for a significant amount of snaps.

Two starting linebackers.

Two starting safeties.

Three key depth pieces, one of whom will probably start.

And that doesn't even include the most important player of all -- Aaron Charles Donald.

Donald will be 29 years old and, assuming health, will probably still be the game's most menacing interior pass-rusher by the time the Rams move into their new stadium in 2020. He is still two seasons away from becoming eligible for free agency, but he already (understandably) wants a new contract, a motivation he made known by skipping organized team activities earlier this summer. It's a complicated dynamic. Donald deserves to be compensated among the game's highest-paid defensive players, but his price tag over these next two years -- he'll make a combined base salary of $10,117,250 -- gives the Rams little incentive to go so high.

Publicly, though, the organization has said the right things.

"Aaron deserves to be paid among the elite players in our game," COO Kevin Demoff told fans at the Rams All-Access event in the middle of June. "That's never been a sticking point for anybody in our organization."

But it's very difficult to juggle so many balls in the air at once, even with nearly $40 million in cap space set up for 2018. Tough decisions are necessary when so many contracts expire simultaneously. The Rams made one already by opting against extending Johnson, who will make $16.74 million in 2017 and had no reason to settle for an extension that wasn't among the highest for his position. But they can't keep losing key pieces from their defense, because they still need to dedicate so much of their resources to finally getting their dreadful offense on track.

For now, Donald is a priority. So is Ogletree, who led the Rams in tackles last year. And so is Joyner, who is expected to contribute as both a free safety and a slot corner this season.

The rest will probably be figured out next year.

Almost every defense Wade Phillips has ever taken over has drastically improved in his first season. He could make the 2017 Rams defense a top-five unit, a possibility that has some, most notably Football Outsiders, believing that the Rams can actually be a .500 team this year. Bad as their offense has been, their defense is legit. But the Rams must keep the core of it intact before it's too late.

(Previously: 5, solidify the offensive line.)