(Reuters) - Institutional Shareholder Services has advised Goldman Sachs ( GS ) investors to reject the board's decision to grant one-time awards to its top two executives, becoming the second prominent proxy adviser to do so.

The combined $160 million stock awards to CEO David Solomon and Chief Operating Officer John Waldron, who is widely considered Solomon's potential successor, were unveiled in January to retain them and ensure stability in the top ranks.

While the rationale could be compelling for some shareholders, the awards lacked "rigorous, pre-set performance-vesting criteria" and their "magnitude and structure" were concerning, ISS said in a report dated Monday.

The pushback highlights a persistent dilemma on Wall Street - balancing fierce competition for top talent with concerns over what some deem to be excessive compensation.

Glass Lewis, another major proxy adviser, has also recommended that investors vote against the pay of top Goldman executives.

Goldman Sachs ( GS ) did not immediately respond to a request for comment outside regular business hours. It had previously said in response to the Glass Lewis opposition that the awards were meant to "retain our current leadership team ... and maintain a strong succession plan" amid intense competition for talent.

Disputes between proxy advisers and banks over issues of corporate governance have escalated in recent years. Last year, such advisers urged JPMorgan Chase and Bank of America to separate the CEO and chair roles, which is a common practice at many banks.

JPMorgan CEO Jamie Dimon has argued that proxy advisers often wield "undue influence".

(Reporting by Niket Nishant in Bengaluru; Editing by Anil D'Silva)