No Dave Dombrowski? No problem for the Tigers -- at least not in the short term.

It's still surprising that owner Mike Ilitch dismissed Dombrowski last August. It's tricky to deconstruct that move, especially since the Red Sox pounced on Dombrowski only two weeks after he cleaned out his office at Comerica Park.

But make no mistake about it: Ilitch was not doing Dombrowski a favor by releasing him to pursue chances elsewhere. Detroit's owner has been clear that winning a World Series is his ultimate goal, and while Dombrowski led the club to the precipice on a pair of occasions, Illitch decided to it was time to give someone else -- longtime lieutenant Al Avila -- a chance to steer the ship.

In fact, Ilitch made it clear he wasn't looking for a change of philosophy when he signed Avila to a five-year contract. He proved it by providing Avila resources that most other general managers can only envy.

• Hot Stove Tracker

The Tigers' moves this offseason haven't been as splashy as the ones Dombrowski made while finding his way around Fenway Park. But score the first round to Avila. Detroit heads my list of most improved teams.

Justin Upton and Jordan Zimmermann were nine-figure bookends to an offseason in which Avila added to the Tigers' strength (the lineup) while addressing the glaring weakness (bullpen). A lot still depends on how aging superstars Justin Verlander and Miguel Cabrera hold up, but manager Brad Ausmus will look a lot smarter with closer Francisco Rodriguez and setup men Justin Wilson and Mark Lowe in the bullpen.

Cameron Maybin, added in a trade with the Braves, is likely to platoon with Anthony Gose in center. Mike Aviles and Jarrod Saltalamacchia bring 17 years of experience to the bench, and Mike Pelfrey adds stability to the back of the rotation.

A ranking of the other most improved teams:

2. Cubs

Depth was a strength for the Cubs during their 97-win season in 2015, but they are much deeper after investing $272 million in Jason Heyward, John Lackey and Ben Zobrist.

Those three guys produced 12.3 WAR between them last season -- and Zobrist's production in Oakland and Kansas City lagged far behind his last six seasons playing for Joe Maddon, when he averaged 6.2 WAR, according to Baseball-Reference.

Epstein traded Starlin Castro to open a hole for Zobrist and brought back a quality arm from the Yankees in Adam Warren. He didn't add a big-ticket arm for a bullpen that was thin in the postseason, but he re-signed Trevor Cahill and imported lefties Rex Brothers and Edgar Olmos and right-handers Jean Machi, Brandon Gomes, Spencer Patton and Andury Acevedo. The competition for jobs in Spring Training should be fierce.

That will be true on the bench, too, as Dexter Fowler, Chris Denorfia and stretch-run addition Austin Jackson represent the only departing free agents.

3. Diamondbacks

It's an oversimplification to accuse GM Dave Stewart of one-stop shopping. But second-year chief baseball officer Tony La Russa did a great job shopping in the starting pitching aisle.

Zack Greinke and Shelby Miller make Arizona relevant again. In fact, between Greinke, Paul Goldschmidt and A.J. Pollock, the D-backs' roster will boast three players who ranked in the top 10 in WAR in 2015.

There are rumors that they aren't done, either. Second baseman Howie Kendrick is a possibility.

4. Red Sox

A lack of a No. 1 starter and a bullpen that was 13th in the American League with a 4.24 ERA contributed to the Red Sox's last-place finish in the division. But by adding Price, Kimbrel and powerful setup man Carson Smith (11.8 strikeouts per nine innings), Dombrowski has put Boston in business again.

Chris Young adds to a deep outfield mix that could help the Red Sox pull off a big midseason trade. They did take a risk by trading innings-eater Wade Miley to the Mariners in the deal that landed Smith and lefty Roenis Elias, but Boston has pitching prospects Henry Owens, Matt Barnes, Brian Johnson and Edwin Escobar stacked up behind Eduardo Rodriguez, who held his own in 21 starts as a rookie.

5. Mariners

Jerry Dipoto knew he wouldn't have much payroll flexibility when he took the Seattle GM job. After all, the Mariners were already holding more than $470 million in future payroll obligations, mostly to Robinson Cano, Felix Hernandez, Kyle Seager and Nelson Cruz. But you can't judge the impact of the move by the size of headline it receives.

Dipoto hit the ground running in the Hot Stove season. He dealt away two potential run producers in Mark Trumbo and Logan Morrison, but he wound up with two potential 200-innings arms in Miley and Nathan Karns, and a more reliable hitter in first baseman Adam Lind (who should improve Seattle's .311 on-base percentage). If they're average, newcomers Chris Iannetta and Steve Clevenger will be major upgrades at catcher.

Dipoto surprised even himself by re-signing Hisashi Iwakuma, who was headed to the Dodgers before questions about his health. He added veterans Steve Cishek and Joaquin Benoit to anchor the bullpen, and Leonys Martin to go get the ball in center field. By re-signing Franklin Gutierrez and adding Nori Aoki, Dipoto gives rookie manager Scott Servais the option of using Cruz as his DH. All together, pretty impressive list of medium and small moves.

Honorable mention: Athletics, White Sox and Giants

It's fashionable to praise San Francisco's addition of Johnny Cueto, Jeff Samardzija and Denard Span, but all three have been around. They come with caution signs. Same goes for not-so-new White Sox third baseman Todd Frazier, who simply seemed worn down at the end of 2015 in Cincinnati. Billy Beane quietly retooled with a series of low-cost moves. His biggest investment was adding Ryan Madson and John Axford to the bullpen, but starters Rich Hill and Henderson Alvarez, first baseman Yonder Alonso and infielder Jed Lowrie should give Bob Melvin a run at a winning season.