Microsoft Corp. Chief Executive Officer Satya Nadella and Activision Blizzard Inc. CEO Bobby Kotick will be in court this week to try to persuade a federal judge in California to reject the Federal Trade Commission’s effort to block their $69 billion deal.

US District Judge Jacqueline Scott Corley is presiding at a five-day hearing in San Francisco starting Thursday over the FTC’s bid to prevent Microsoft from acquiring Activision.

Other top Microsoft executives, including Chief Financial Officer Amy Hood and Phil Spencer, executive vice president for gaming, are expected to take the witness stand. Activision’s Chief Financial Officer Armin Zerza is also expected to testify.

By appearing in court, the executives will defend the blockbuster deal, which would catapult Microsoft to the No. 3 position in the global games market after Tencent Holdings Ltd. and Sony Group Corp., and submit to tough questioning from FTC lawyers.

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