But a bleeding ulcer that caused severe fatigue put the eight-time All-Star on the 15-day disabled list. And for the first time in nine seasons, the Mariners will begin a season without their star outfielder being their first batter.
"Endy played well this spring and showed he can do some things with the bat beyond just hit," Wakamatsu said prior to the Mariners' late Sunday afternoon workout. "He gives us a viable candidate to replace Ichiro."
The left-handed-hitting Chavez finished Spring Training on a hitting binge, going 18-for-31 in the nine games he played after returning to the Mariners from a two-week hiatus to play for Venezuela in the World Baseball Classic.
Chavez said he feels comfortable batting first, which he did during the Classic, and during the Venezuela Winter League for the past several seasons.
"It is a lot of work, and my job is to put the ball in play, get on base for the big guys, and help this team win a lot of games," he said. "I play small ball."
The first lineup during the Wakamatsu era starts with Chavez at the top, followed by center fielder Franklin Gutierrez, designated hitter Mike Sweeney, third baseman Adrian Beltre, right fielder Ken Griffey Jr., second baseman Jose Lopez, first baseman Russell Branyan, catcher Kenji Johjima and shortstop Yuniesky Betancourt.
Ace right-hander Felix Hernandez will make his second career Opening Day start, while the Twins counter with left-hander Francisco Liriano in the 5:10 p.m. PT game.
The lineup on Monday night figures to be just one of many during the season -- with or without Ichiro.
"I think it's going to depend on whether it's a right- or left-handed pitcher," he said. "I'll probably have 120 lineups this year because we have some versatility there and obviously how they are playing."
Ichiro surely would bat leadoff most -- if not all the time -- when he returns. The No. 2 spot could be fluid, with Gutierrez, Lopez and possibly Betancourt batting there. The 3-4-5 spots would change, according to the right-left aspect, but still involve Beltre, Griffey, Sweeney and Branyan most of the time.
"We talked this spring about guys like Sweeney and Junior bringing maturity to the lineup and power potential," Wakamatsu said, "and you have Russell in there this spring showing that he can do some special things.
"We will rely heavily on those guys, but I like our [run-scoring potential] having Johjima hitting that deep, and Betancourt. Yuni is a .280 career hitter. This lineup gives us some depth all the way through the lineup.
"One-through-nine, this is a better lineup than people give us credit for."
Batting first is something new for Chavez. He played 133 games for the Mets last season and batted second, fourth, fifth, sixth, seventh, eighth and ninth.
But there is something the Mariners saw in him this spring that led them to put him No. 1.
"He can do a lot of things," hitting coach Alan Cockrell said. "He works the count well, getting deep into counts. He has a tremendous short game, and can hit balls into the gaps. He brings a lot to the table."
Chavez had more at-bats (107) batting second than any other spot in the lineup, but had 85 at-bats batting eighth, 39 batting ninth and 27 batting seventh.
He had a .319 on-base percentage batting second, compared to Ichiro's .360 OBP last season as the leadoff hitter.
"He brings the bunt with him to the right side, which is very effective against left-handers," Cockrell said. "He can just do a lot of things."