3 moves the Mariners need to make next to become contenders

Seattle Mariners general manager Jerry Dipoto pulled off the first stunning blockbuster trade of the winter Wednesday night when he sent right-hander Taijuan Walker and shortstop Ketel Marte to the Arizona Diamondbacks for shortstop Jean Segura, outfielder Mitch Haniger, and left-hander Zac Curtis.

The trade shores up an immediate area of need for the Mariners at shortstop, where Segura's bat - assuming he repeats his career year of 2016 - is far better than the cumulative .613 OPS and four homers put up by Seattle shortstops last season. Haniger, now ranked as the team's No. 14 prospect, got a taste of the majors in 2016 and could contribute in the coming year, while Curtis might have a future as a left-handed relief option for skipper Scott Servais.

Still, after all that, Dipoto has more to do to improve his club if he's going to end the Mariners' major-league worst 15-year playoff drought in 2017. Here's three more moves the Mariners need to make next to become legitimate contenders.

Starters, starters, starters

Every trade has its drawbacks; in this case, netting Segura's production cost Seattle the 24-year-old Walker and left a hole in the rotation. Felix Hernandez is still there, of course, but the miles are beginning to add up on his arm, while veteran Hisashi Iwakuma - the only Mariners hurler to make 30 starts in 2016 - has dealt with some arm issues in the past few years. Dipoto needs to find some more rotation help, and he might want to grab more than one starter, too. If he doesn't want to trade from the thin farm system, then going short-term with free-agent veterans such as Edinson Volquez, Doug Fister, or even Jason Hammel while hoping they thrive in pitcher-friendly Safeco Field is the most logical route to take here. The Mariners could do a whole lot worse.

Sign Mike Napoli

Napoli has already been linked to the Mariners, and they're reportedly seriously interested in signing him. If the feeling is mutual, Napoli's 30-homer power would give the Mariners quite the middle of the order in 2017 alongside Robinson Cano, Nelson Cruz, and Kyle Seager, in some order. He'd also fill up a glaring hole at first base: The platoon partners at first from last year, Adam Lind and Dae-Ho Lee, are both free agents and very unlikely to return, while youngster Dan Vogelbach - who profiles as more of a strict DH type - is the current first baseman. While his power numbers might take a small hit at Safeco, his bat would still represent a major upgrade for the Mariners, and one who can help wreak havoc on opposing pitching.

Another outfielder

There's still a need for one or two more bats in the outfield, especially if the Mariners are ready to transition the defensively-challenged Cruz into a permanent DH role. They could try for one of the higher-end options like Ian Desmond, who could shift to a corner and would vastly improve their lineup, but the likelier options could come from secondary moves. Carlos Gomez would fit here, as would a trade - perhaps using infielder Danny Valencia, acquired earlier this offseason, as bait, especially if Napoli is brought on board - for an available corner outfielder like Brett Gardner. There's also the need for a lefty-masher to platoon with Seth Smith in left, and the Mariners might be wise to grab Steve Pearce for that role. Any of these bats would fit perfectly into the Mariners' outfield mix and help this talented team push the Rangers in the AL West next year.