After signing with the Boston Celtics this offseason, Danilo Gallinari was ready and excited for his debut. Unfortunately, his start with the C's will have to wait.

During the FIBA World Cup Qualifiers, Gallinari suffered a scary non-contact injury while playing for Italy. Although he avoided a disastrous blow to his ACL, the video of his injury had many fearing the worst.

The veteran was actually diagnosed with a torn left meniscus, which isn't the worst-case scenario, yet far from the best. As a result, the Celtics' depth will be tested much earlier in the season, so who's going to step up?

With an improved roster and a good amount of talent, Boston has answers. Here are three Celtics who can fill the Gallinari gap while he sits out for an indefinite amount of time.

3 Celtics players who must step up after Danilo Gallinari injury

3. Grant Williams

Following the best year of his young career, Williams has assured an increase in minutes in Gallinari's absence.

The 6-foot-6 power forward averaged more playing time last year (24.4 minutes per game) than his previous two seasons with the C's, so it's no surprise that he posted his best per-game marks to date in points, assists, rebounds, and blocks. His most notable improvement was in something Gallinari also prides himself on: three-point shooting.

Williams was a corner-three assassin, regularly splashing from that spot on the court and hitting 41 percent of his threes on the year. That's a substantial jump from his lousy 25 percent three-point percentage in 2019, so he has undoubtedly proven his ability to grow as a player.

Given the recent injury news, the 2022-23 season will be another chance for Williams to improve and show his worth. He's a better defender than Gallinari and can fill the shooting role that the Italian forward would usually serve. Plus, Williams will be a free agent in 2023 and has an added incentive to perform in order to earn a sizable contract.

2. Malcolm Brogdon

Although the other new Celtic doesn't exactly match up position-wise with Gallinari, that doesn't mean he can't step up.

With the 6-foot-10 Gallinari sidelined, Boston might have to default to a smaller overall lineup. If so, Brogdon still has the defensive prowess to guard almost any non-big player. Moreover, with a solid outside shot and great court vision, the former rookie of the year can score enough to make up for Gallinari's absence.

However, this is all dependent on whether or not Brogdon can stay healthy himself. Last year he only played 36 games due to an Achilles injury, so remaining in the Celtics' rotation will be a huge help on its own. While Jayson Tatum and Jaylen Brown could also see an increase in minutes with Gallo down, it's crucial that players like Brogdon and Williams serve their offensive duties well.

As we saw last season, early fatigue from too many minutes was devastating to Boston — and Tatum in particular — in the NBA Finals. So, if Brogdon can take some of that added weight stemming from Gallinari's injury off of the shoulders of Tatum and Brown, that could lead to greater success down the road for the Celtics.

1. Sam Hauser

Perhaps the biggest question mark on this list is Sam Hauser, who is coming off a newly minted three-year contract with the Celtics. With that security now, hopefully the sharp-shooting Hauser can come into his own because so far fans haven't seen much.

More minutes seem to be on the horizon for Hauser and in some ways, he excels in what Gallinari excels in. Hauser can clearly connect from deep, as he's a good spot-up shooter who converted on 43 percent of his threes last season. Yet, that comes from a small sample size of 26 games, so Hauser's full potential is largely unknown.

If he can work on creating more shots and even posting up a little, Hauser could become a similar player to Gallinari. But, the Celtics really just need him to hit his shots and not end up as a defensive liability.

Overall, Gallinari's pre-season injury is disappointing and frustrating, however, it should wake up Boston from any post-Finals hangover. With this tough luck, the Celtics are going to be tested right out of the gate in the 2022-23 NBA season.