Opening Day for Major League Baseball is March 28 for most teams. But the Seattle Mariners and Oakland Athletics get the party started on Wednesday in Japan, as the AL West rivals face off at the Tokyo Dome, with a 5:35 a.m. first pitch for the 2019 Japan Opening Series. The latest Mariners vs. Athletics odds for the first regular season game have favored Oakland at -134 on the money line, meaning you'd need to risk $134 to win $100, while Seattle is at +$110 (risk $100 to win $110). The legendary Ichiro Suzuki returns to the field for Wednesday's game in Tokyo, so before laying any Mariners vs. Athletics picks of your own, you'll want to see the 2019 Japan Opening Series predictions from SportsLine MLB expert Adam Thompson.

Thompson raked in the winning as SportsLine's top MLB handicapper last year, hitting on 61 percent of his money line picks for a massive profit of $4,062 to $100 players. He ended the season on a 22-4 run, including hitting every World Series game. 

Thompson, who covered major sports for 20 years as a writer and columnist before joining SportsLine as a senior writer and handicapper, cites deeply-researched stats and trends you haven't considered to build his MLB success.

Now, Thompson has studied the Mariners vs. Athletics in Japan. He's considered that the A's went 97-65 last year and made the AL playoffs. For that reason, it was a relatively quiet offseason for Oakland, which returns most of its key players. That includes Khris Davis, who hit a whopping 48 home runs in 2018, his third year in a row with 40-plus.

The Mariners, meanwhile, disassembled their core, trading away Robinson Cano, Jean Segura and pitchers James Paxton and Edwin Diaz. Oakland may be a lot closer to regular season form than Seattle.

Mike Fiers gets the start for Oakland -- he went 12-8 with a 3.56 ERA for the A's and Tigers in 2018. He'll be relieved by a bullpen that ranked No. 2 in MLB last year in average allowed (.220), led by All-Star closer Blake Treinen, who had a tiny 0.78 ERA in 80.1 innings thrown.

Just because the A's are locked in for another fruitful season doesn't mean they're the best value on the money line in Tokyo on Wednesday. 

Seattle made seven trades in the offseason as part of a youth movement. The Mariners had the worst offense of any above-.500 team in baseball last year, so fresh blood may be just what the doctor ordered. They added sluggers Jay Bruce and Domingo Santana, showing that the franchise isn't necessarily in "tank mode."

Starter Marco Gonzales was a mediocre 1-1 with a 4.70 ERA against Oakland last season, but his propensity to keep the ball in the yard is an asset against the swing-for-the-fences A's lineup.

Certainly, Seattle will have the crowd on its side with the addition of Ichiro into Wednesday's starting lineup. Ichiro, one of the more-beloved sports figures in Japan's history, is a 17-time All-Star (seven in Nippon Professional Baseball, 10 in MLB). The Tokyo Dome crowd is expected to give him a hero's welcome. 

Thompson has studied this matchup from every angle and unearthed a hidden x-factor you're not even thinking about that determines which side you need to jump on. He's only sharing what it is, and who to back, at SportsLine. 

So who wins Athletics vs. Mariners? And what hidden x-factor makes one side a must-back? Visit SportsLine now to find out which side of Mariners-A's has all the value, all from the MLB expert who hit 61 of his MLB money line picks in 2018 for a profit of more than $4,000 to $100 players.