The Barcelona forward has scored just two goals in eight games for his club this season, while he has netted three times in 12 World Cup qualifiers.
Reports had suggested Suarez needed surgery on a problematic knee problem but Tabarez says the 30-year-old is ready to go.
"If it [the injury] was big enough as to be making sacrifices, they would have put him through surgery already," he told a news conference on Sunday.
"He's in a period where he made an amazing recovery but beyond that he didn't play.
"And a player who comes here to face Argentina [in late August] and hasn't played in three or four weeks, he has to make a sacrifice to make up for that lack of physical preparation.
"From that point of view, Luis already passed a lot of tests and that's why we never discard him. He's the first one not giving up on himself, he's stubborn in a very positive way."
Uruguay are second in CONMEBOL qualifying ahead of hosting Bolivia on the final matchday on Tuesday.
Suarez last scored for the national team in October last year but Tabarez, whose team are assured of at least a play-off spot, backed the forward.
We keep sticking with him because he's a player who can disappear from time to time," he added.
"How many times during the last qualifiers did we think about taking him out and then suddenly he improved and scored goals.
"He's a player not to be categorised by form. He has an ability that amazes us when he plays. So he's fit to play and the rest we can reduce to a bad spell.
"Football players have these spells, football teams have these spells and luckily, they always end."